i ii - nature...v 0.0 quartet 1.498 1.777 ts (461 i) 4.1 kcal/mol –121.9 kcal/mol quartet quartet...

2.536(2.351)

2.279

(2.239)

I'

0.0 (+5.4) kcal/mol

quintet (triplet)

I

0.0 (+4.1) kcal/mol

quintet (triplet)

2.492(2.348)

2.106

(2.077)

2.105

(2.175)

2.360

(2.497)

1.867

(2.005)

1.126

(1.115)

2.356(2.508)

2.276(2.286)

1.857

(2.076)

1.131(1.112)

Fe

O

Si

C

H

Cl

II

0.0 (+4.3) kcal/mol

triplet (quintet)

II'

0.0 (+1.9) kcal/mol

triplet (quintet)

N

Supplementary Figure S1 | Stable structures of I, I', II, and II' optimized at the

B3LYP*/6-311+G** level of theory.

2

Supplementary Figure S2 | Energy profile of a possible catalytic cycle on the

transformation of N2 into N(SiMe3)3 catalyzed by [Fe(SiMe3)2(thf)] (I).

Si represents trimethylsilyl radical. The energy change and activation energy (in parenthesis)

for each reaction step were calculated at the B3LYP*/6-311+G** level of theory. The

energies are presented in kcal/mol.

thf

Fe NSi

Si

thf

Fe NSi

Si

N

Si

Si

thf

Fe NSi2

Si

thf

Fe NSi2Si

Si

Fe thf

Si

Si

thf

Fe NSi3

Si

thf

Fe NSi3

Si

Si

N

thf

Fe NSi

Si

N

Si

–12.1(no barrier)

–21.3(3.1)

SiN2

–36.6(0.9)

Si

–1.6(12.0)

Si

I (triplet) II (triplet) III (quartet) IV (triplet)

X (quintet)

Si

–22.3(0.6)

VII (quintet)

Si migration

+7.6(19.0)

Si

VIII (quartet)

IX (quartet)

–16.6(0.4)

thf

Fe NSi

Si

NSi3

–121.9(4.1)

N–N cleavage

V (quartet)

thf Fe NSi2

VI (quartet)

Si migration

–35.6(no barrier)

–22.3(0.6)

Si

N(SiMe3)3

N(SiMe3)3

3

1.865

1.126

4.443

II – SiMe3 TS (123i) III

O

NNFe

Si

C

2.5311.153

1.819

1.805

1.204

1.742

0.0 3.1 kcal/mol –21.3 kcal/mol

quartet quartet quartet

Supplementary Figure S3 | Energy profile and optimized structures for the addition

of Me3Si radical to II.

4

1.742

1.206

4.930

III – SiMe3 TS (34i) IV

3.199

1.206

1.754

1.814 (1.818)

1.328(1.325)

1.741(1.731)

0.0 0.9 kcal/mol –32.6 (–36.5) kcal/mol

quintet quintet quintet (triplet)


of Me3Si radical to III.

5

IV – SiMe3 TS (148i) V



2.615

1.343

1.7696.269

1.325

1.732

1.8801.498

1.777


of Me3Si radical to IV.

6

V

0.0

quartet

1.498

1.777

TS (461i)

4.1 kcal/mol –121.9 kcal/mol

quartet quartet

1.829

1.707

VI – N(SiMe3)3

7.722

1.869

Supplementary Figure S6 | Energy profile and optimized structures for the N-N bond

cleavage of V and the generation of N(SiMe3)3.

7

2.439

6.227

4.532

VII – SiMe3 TS (18i) VIII




of Me3Si radical to VII.

8

IXTS (150i)VIII

2.152

4.626

19.0 kcal/mol0.0

quartetquartetquartet

2.244

2.336

2.551

7.6 kcal/mol

N–Fe–Si = 170.4°

2.439

1.990

2.208

1.947

1.847

Supplementary Figure S8 | Energy profile and optimized structures for the Me3Si

migration of VIII yielding IX.

9

6.619 4.533

IX – SiMe3 TS (41i) X


quintet quintet quintet

5.1274.697 4.834

2.546


of Me3Si radical to IX.

10

5.127

3.369

X TS (46i) I – N(SiMe3)3


quintet quintet quintet

2.378 2.460

2.107 7.654

Supplementary Figure S10 | Energy profile and optimized structures for the release

of N(SiMe3)3 from X.

11

Supplementary Table S1 | [Fe(CO)5]-catalyzed formation of N(SiMe3)3 from N2.a

—————————————————————————————————————————————

Fe(CO)5 solvent temp. amount (mmol)b

equiv of 1 based run ————————————————— (mmol) (mL) (°C) 1 2 3 4 on Fe atom

—————————————————————————————————————————————

1 0.10 THF (40) rt 2.54 0.50 5.09 8.98 25

2 0.03 THF (40) rt 0.09 1.98 0.42 3.02 3

3 0.50 THF (40) rt 6.18 0.78 6.44 3.53 12

4 0.10 THF (20) rt 2.20 0.58 5.22 13.31 22

5 0.10 THF (60) rt 0.77 0.30 2.14 3.78 8

6 0.10 THF (40) 40 2.56 1.30 5.23 21.32 26

7 0.10 THF (40) 60 1.60 1.32 4.73 20.92 16

8c 0.10 THF (40) rt 2.35 3.89 0.89 10.72 24

9 0.10 hexane (40) rt 0 2.15 0 0 0

10 0.10 benzene (40) rt 0 0 0 0 0

11 0.10 Et2O (40) rt 0 0 0 0 0

12 0.10 DME (40) rt 0.18 0 0 0 2

13 0.10 dioxane (40) rt 0.02 0.57 0 0 0.2

14d 0.10 THF (40) rt 0.50 20.66 0.26 0 5

15e 0.10 THF (40) rt 0.03 1.80 0.16 9.62 0.3

16f 0.10 THF (40) rt 0.01 0.62 0.12 1.11 0.1

17g 0.10 THF (40) rt 2.01 0.97 3.41 10.03 20

————————————————————————————————————————————— a All reactions using Na (60 mmol) and Me3SiCl (60 mmol) were carried out in the presence of

[Fe(CO)5] under atmospheric pressure of N2. b Determined by GLC analysis. c For 100 h. d Li was

used in place of Na. e The reaction was carried out under argon atmosphere. f The reaction was

carried out under dry air. g The reaction was carried out in the presence of galvinoxyl (0.10 mmol).

N2 (1 atm)

+ 6 Na(60 mmol)

6 Me3SiCl(60 mmol)

[Fe(CO)5]

(0.10 mmol)

solvent6 NaCl+ +2 N(SiMe3)3

1temp

20 h

2 3

CH3CH2CH2CH2OSiMe3Me3SiSiMe3

4

Me3SiCH2CH2CH2CH2OSiMe3

12

Supplementary Table S2 | Fe-catalyzed formation of N(SiMe3)3 from N2.a

—————————————————————————————————————————————

amount (mmol) b equiv of 1 based run catalyst ———————————————————— 1 2 3 4 on Fe atom

—————————————————————————————————————————————

1 [Fe(CO)5] 2.54 0.50 5.09 8.98 25

2 [Fe2(CO)9] c 0.86 1.34 2.59 7.01 9

3 [Fe3(CO)12] d 1.20 0.26 2.11 5.77 12

4 [Fe(SiMe3)2(CO)4] 2.94 0.69 5.07 8.85 29

5 [CpFe(CO)2]2 e 1.69 0.68 3.38 14.34 17

6 [CpFe(CO)2I] 2.73 0.69 4.74 14.59 27

7 [Cp2Fe] 1.32 1.05 2.17 13.05 13

8 [Cp'2Fe] f 2.32 1.14 3.98 17.01 23

9 [Cp''2Fe] g 3.41 0.28 5.45 4.89 34

————————————————————————————————————————————— a All reactions using Na (60 mmol) and Me3SiCl (60 mmol) were carried out in the presence of a

catalyst (0.10 mmol) under atmospheric pressure of N2 at room temperature for 20 h in THF (40 mL).

b Determined by GLC analysis. c [Fe2(CO)9] (0.05 mmol) was used. d [Fe3(CO)12] (0.033 mmol)

was used. e [CpFe(CO)2]2 (0.05 mmol) was used. f [Cp'2Fe] = [(η5-C5H4SiMe3)2Fe]. g [Cp''2Fe] =

[{η5-C5H2(SiMe3)3}2Fe].

N2 (1 atm)

+ 6 Na(60 mmol)

6 Me3SiCl(60 mmol)

catalyst (0.10 mmol)

THF6 NaCl+ +2 N(SiMe3)3

1rt

20 h

2 3


4


13

Supplementary Table S3 | Time profile of [Fe(CO)5]-catalyzed formation of

N(SiMe3)3 from N2.a

—————————————————————————————————————————————

amount (mmol)b t (h) ———————————————————————————————

1 2 3 4

—————————————————————————————————————————————

0 0 0 0 0

2 0.11 0 0 0.40

4 0.34 0 0.11 0.98

6 0.52 0 0.29 1.80

9 0.77 0 0.68 3.47

12 1.06 0.09 0.68 3.91

20 2.21 0.25 2.54 6.96

24 2.26 0.24 2.56 6.96

—————————————————————————————————————————————

a Reaction using Na (60 mmol) and Me3SiCl (60 mmol) were carried out in the

presence of Fe(CO)5 (0.10 mmol) under atmospheric pressure of N2 at room

temperature in THF (40 mL). b Determined by GLC analysis.

N2 (1 atm)

+ 6 Na(60 mmol)

6 Me3SiCl(60 mmol)

[Fe(CO)5]

(0.10 mmol)6 NaCl+ +2 N(SiMe3)3

1

2 3


4


THF

rt

20 h

14

Supplementary Table S4 | Cartesian coordinate of I in the triplet state. Units are presented in Å.

SCF energy = -2314.19197075 hartree

ZPE = 0.336802 hartree

--------------------------------------------------------

Atom Coordinates (Angstroms)

X Y Z

--------------------------------------------------------

Fe 6.533813 1.946462 0.314317

C 4.139856 -1.603915 -0.543552

C 5.504317 -2.127785 -1.020134

C 6.317728 -0.844699 -1.172231

O 5.777586 0.071822 -0.164969

C 4.534366 -0.464803 0.391808

H 3.558256 -1.221507 -1.389063

H 3.542489 -2.363935 -0.033690

H 5.443892 -2.686517 -1.957423

H 5.951032 -2.780063 -0.262006

H 7.384407 -0.962853 -0.972232

H 6.181129 -0.377542 -2.152556

H 3.808320 0.350496 0.434083

H 4.743565 -0.818373 1.407408

Si 7.830548 3.029528 1.954344

C 9.706561 2.799075 1.655331

H 10.046037 3.339721 0.766033

H 10.280137 3.172439 2.514643

H 9.964808 1.742235 1.519286

C 7.569536 4.871767 2.385860

H 7.861602 5.532683 1.562965

H 6.520985 5.083821 2.624594

H 8.172736 5.145735 3.261936

C 7.454503 2.082200 3.588314

H 6.413481 2.217953 3.904506

H 7.636947 1.005267 3.489333

H 8.097962 2.452001 4.399282

Si 6.749771 3.697980 -1.234141

C 6.178161 2.991663 -2.931047

H 5.164274 2.577096 -2.879301

H 6.172732 3.785148 -3.691892

H 6.848684 2.200247 -3.287026

C 5.558707 5.143954 -0.856042

H 4.520190 4.799833 -0.786946

H 5.807355 5.641301 0.086645

H 5.607405 5.895068 -1.656318

C 8.463417 4.466647 -1.578331

H 8.848271 5.017455 -0.714042

H 9.204358 3.702770 -1.840285

H 8.397946 5.169809 -2.419722

--------------------------------------------------------

15

Supplementary Table S5 | Cartesian coordinate of I in the quintet state. Units are presented in Å.



--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe 6.811259 2.455680 0.089014

C 4.295191 -1.117584 0.718203

C 4.357993 -1.108730 -0.817966

C 4.783323 0.323750 -1.124942

O 5.614737 0.724329 0.016200

C 5.491552 -0.253431 1.102925

H 3.363265 -0.659839 1.067209

H 4.362021 -2.121537 1.144932

H 3.404204 -1.361007 -1.288198

H 5.112208 -1.818134 -1.175401

H 5.383368 0.434508 -2.029321

H 3.931033 1.009441 -1.171843

H 5.371759 0.299579 2.035490

H 6.422718 -0.828334 1.142151

Si 7.985841 2.926390 2.236076

C 9.883342 2.703978 2.101467

H 10.306850 3.344546 1.319155

H 10.378571 2.962397 3.047576

H 10.151919 1.669165 1.857019

C 7.718392 4.727554 2.828326

H 8.062672 5.451214 2.080332

H 6.659348 4.936090 3.021487

H 8.271976 4.921103 3.757325

C 7.452359 1.825059 3.718595

H 6.387899 1.948307 3.954156

H 7.631423 0.760601 3.523370

H 8.020179 2.092178 4.620560

Si 6.939519 3.855583 -1.969187

C 6.257592 3.026921 -3.564053

H 5.189115 2.793119 -3.481162

H 6.379057 3.696112 -4.427155

H 6.788167 2.095160 -3.796015

C 5.982905 5.507050 -1.810837

H 4.910011 5.338054 -1.659219

H 6.343349 6.099540 -0.961809

H 6.099654 6.118294 -2.716311

C 8.742564 4.341954 -2.392963

H 9.217046 4.886947 -1.568657

H 9.360561 3.460112 -2.600018

H 8.775256 4.988218 -3.280851

--------------------------------------------------------

16

Supplementary Table S6 | Cartesian coordinate of I' in the triplet state. Units are presented in Å.



--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe -0.073055 -0.970854 -0.001269

Si 0.564427 0.551170 1.672743

C 2.463261 0.590647 1.988444

H 2.849346 -0.420881 2.164010

H 3.010497 1.010412 1.137422

H 2.696682 1.197508 2.875751

C -0.161235 -0.062663 3.352376

H 0.136905 -1.098182 3.553373

H 0.187435 0.564708 4.187272

H -1.257526 -0.036639 3.342336

C 0.042087 2.403795 1.632173

H 0.325594 2.903763 2.569968

H 0.512844 2.949264 0.806357

H -1.044060 2.504119 1.515566

Si 0.522407 0.512116 -1.723922

C 2.172104 1.504055 -1.718639

H 2.201390 2.251769 -0.918193

H 3.032869 0.838658 -1.578052

H 2.307946 2.029993 -2.675063

C -0.830922 1.831886 -2.090959

H -0.935463 2.550351 -1.270754

H -0.586831 2.393507 -3.004808

H -1.807944 1.356694 -2.241060

C 0.633645 -0.492595 -3.368014

H 0.806324 0.174193 -4.226955

H 1.453983 -1.219536 -3.331874

H -0.289952 -1.054317 -3.549445

Cl -0.929140 -3.039190 0.029117

--------------------------------------------------------

17

Supplementary Table S7 | Cartesian coordinate of I' in the quintet state. Units are presented in Å.



--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe 0.315298 -0.649656 -0.015796

Si 0.681418 0.568280 2.178797

C 2.482758 0.447087 2.853870

H 2.770534 -0.598462 3.018610

H 3.202772 0.875951 2.145831

H 2.589929 0.982292 3.809601

C -0.400843 -0.054248 3.644226

H -0.233647 -1.122391 3.826709

H -0.175128 0.491738 4.572848

H -1.468852 0.073127 3.428501

C 0.341534 2.465079 2.128782

H 0.526877 2.931349 3.108197

H 0.982010 2.965722 1.392043

H -0.698805 2.673871 1.849548

Si 0.493527 0.543114 -2.246243

C 2.056357 1.659140 -2.412739

H 2.092527 2.412739 -1.616507

H 2.976034 1.065231 -2.340605

H 2.071101 2.187352 -3.378053

C -0.963509 1.749231 -2.619859

H -1.047361 2.521931 -1.845626

H -0.826658 2.255163 -3.587646

H -1.920983 1.214694 -2.652691

C 0.566208 -0.586064 -3.803567

H 0.634116 0.006409 -4.728702

H 1.434748 -1.254695 -3.764215

H -0.325465 -1.220920 -3.869778

Cl -0.152876 -2.879315 0.052364

--------------------------------------------------------

18

Supplementary Table S8 | Cartesian coordinate of II in the triplet state. Units are presented in Å.



--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe 0.532224 -0.041515 9.721906

Si 2.128326 -0.683506 11.336733

Si -0.760929 0.998988 11.432620

N 2.434755 1.354023 7.881015

N 1.728042 0.811716 8.569109

C -1.895706 -0.135384 12.471968

H -2.529568 -0.769253 11.840441

H -1.319694 -0.794304 13.129160

H -2.561581 0.469728 13.101959

C -1.950611 2.078304 10.371956

H -2.558128 1.472173 9.689295

H -2.640283 2.625807 11.029536

H -1.409772 2.819143 9.772334

C 0.059411 2.209458 12.655749

H -0.713574 2.750401 13.218103

H 0.699419 1.699363 13.382967

H 0.674400 2.951748 12.135268

C 1.638036 -1.418660 13.026912

H 1.237638 -0.664327 13.712025

H 0.883563 -2.206523 12.922306

H 2.519819 -1.863657 13.507344

C 3.504982 0.587626 11.662618

H 3.132150 1.448256 12.227521

H 4.316788 0.131986 12.245102

H 3.931235 0.963976 10.726766

C 2.912658 -2.146773 10.365702

H 3.746775 -2.559875 10.950054

H 2.199715 -2.962123 10.196291

H 3.312504 -1.837174 9.394098

C -1.759128 -1.520118 6.234437

C -2.683672 -1.948783 7.386059

C -1.743158 -1.922536 8.588026

O -0.766646 -0.876365 8.291687

C -0.883633 -0.460017 6.894752

H -1.149977 -2.365393 5.896167

H -2.302527 -1.124986 5.372367

H -3.130010 -2.934923 7.234909

H -3.494098 -1.223661 7.517195

H -2.229038 -1.667867 9.531855

H -1.198378 -2.865925 8.706015

H 0.124847 -0.389351 6.483482

H -1.351699 0.530390 6.875144

--------------------------------------------------------

19

Supplementary Table S9 | Cartesian coordinate of II in the quintet state. Units are presented in Å.



--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe 0.547454 0.378988 9.785442

Si 2.184120 -1.055532 11.010582

Si -0.922889 1.687333 11.324706

N 1.757679 2.066839 7.469245

N 1.270163 1.403085 8.220402

C -2.245471 0.589949 12.168374

H -2.950167 0.172157 11.439118

H -1.790346 -0.247609 12.708800

H -2.829306 1.175823 12.891441

C -1.881285 3.118944 10.487347

H -2.556768 2.753413 9.704956

H -2.489497 3.661754 11.224309

H -1.199288 3.841401 10.024219

C 0.094822 2.480713 12.733708

H -0.559419 3.039961 13.416335

H 0.624214 1.724895 13.324632

H 0.844675 3.178770 12.344363

C 1.373984 -1.986699 12.472156

H 0.921023 -1.291570 13.187860

H 0.586736 -2.672807 12.137574

H 2.122480 -2.581043 13.013827

C 3.593441 -0.004261 11.759772

H 3.204260 0.765728 12.435279

H 4.286545 -0.634211 12.333912

H 4.173962 0.503647 10.980906

C 3.029600 -2.393666 9.930262

H 3.734682 -2.987935 10.527886

H 2.299672 -3.086026 9.494144

H 3.592059 -1.943874 9.103814

C -2.043098 -1.715735 6.742596

C -1.890618 -2.795028 7.827309

C -1.472442 -1.973846 9.042557

O -0.689590 -0.867406 8.502831

C -0.893543 -0.762303 7.063178

H -1.976308 -2.113851 5.726851

H -3.006252 -1.204291 6.845436

H -1.102898 -3.505670 7.554579

H -2.810855 -3.357000 8.006159

H -2.334446 -1.555909 9.574618

H -0.840062 -2.510796 9.752181

H 0.037926 -1.058810 6.567640

H -1.109467 0.282564 6.827649

--------------------------------------------------------

20

Supplementary Table S10 | Cartesian coordinate of II' in the triplet state. Units are presented in Å.



--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe -0.239244 -0.957871 0.011947

Si 0.585459 0.611459 1.573098

C 2.449497 0.458654 1.984490

H 2.718807 -0.595374 2.114254

H 3.076939 0.866314 1.184130

H 2.693310 0.994991 2.913272

C -0.329518 -0.022485 3.145107

H -0.143546 -1.089660 3.304160

H 0.023205 0.528312 4.030169

H -1.413553 0.121528 3.068359

C 0.219658 2.496272 1.576208

H 0.512219 2.932410 2.542404

H 0.761091 3.035623 0.791201

H -0.850467 2.686145 1.431906

Si 0.358688 0.662659 -1.590592

C 2.100480 1.468124 -1.670171

H 2.251124 2.227112 -0.894494

H 2.884292 0.711223 -1.547861

H 2.249796 1.953659 -2.645490

C -0.858496 2.079041 -2.007948

H -0.848599 2.859169 -1.238968

H -0.594617 2.547687 -2.966863

H -1.884409 1.701854 -2.083798

C 0.340908 -0.493985 -3.136650

H 0.673773 0.063753 -4.024818

H 1.008434 -1.354372 -3.011551

H -0.664951 -0.879991 -3.336035

Cl 0.438363 -3.039253 0.636780

N -2.045122 -0.802406 -0.393324

N -3.155671 -0.736971 -0.597427

--------------------------------------------------------

21

Supplementary Table S11 | Cartesian coordinate of II' in the quintet state. Units are presented in Å.



--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe -0.037825 -0.490354 0.026511

Si 0.283580 0.800435 2.152127

C 2.119922 1.258496 2.511367

H 2.745370 0.358884 2.562753

H 2.532921 1.897140 1.720710

H 2.220670 1.796238 3.466245

C -0.273441 -0.142236 3.736282

H 0.232647 -1.111771 3.812234

H -0.049644 0.433723 4.647147

H -1.352599 -0.339755 3.719445

C -0.634114 2.492119 2.278751

H -0.428637 2.983971 3.241395

H -0.322654 3.176075 1.479718

H -1.721016 2.366478 2.193560

Si 0.453647 0.686547 -2.133517

C 2.333945 0.959232 -2.449682

H 2.782435 1.584588 -1.667784

H 2.872283 0.003517 -2.450070

H 2.513734 1.449462 -3.418395

C -0.302587 2.448332 -2.337367

H 0.044189 3.125079 -1.546657

H -0.025450 2.892096 -3.305497

H -1.398458 2.421780 -2.284638

C -0.143485 -0.252868 -3.705528

H 0.153043 0.273006 -4.625874

H 0.278540 -1.264220 -3.740356

H -1.235879 -0.356120 -3.714471

Cl 0.436888 -2.725261 0.104464

N -2.112085 -0.509328 -0.057203

N -3.215550 -0.381073 -0.107152

--------------------------------------------------------

22

Supplementary Table S12 | Cartesian coordinate of II-SiMe3 in the quartet state. Units are presented in Å.



--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe 0.702045 0.308253 10.108866

Si 2.034296 -0.631564 11.817757

Si -0.967173 0.860788 11.727462

N 2.029851 1.420821 9.417707

N 2.816656 2.112655 9.005173

C -2.156738 -0.535143 12.267652

H -2.606987 -1.049176 11.409780

H -1.646855 -1.290582 12.874019

H -2.978594 -0.122234 12.868059

C -2.044926 2.097196 10.720992

H -2.474500 1.635466 9.823886

H -2.880003 2.454232 11.339804

H -1.471344 2.975609 10.403943

C -0.473623 1.798608 13.311192

H -1.371359 2.166201 13.826228

H 0.076061 1.166431 14.016013

H 0.157291 2.663268 13.078189

C 1.299122 -1.770032 13.158920

H 0.732250 -1.217092 13.914947

H 0.629709 -2.520701 12.724339

H 2.107607 -2.302790 13.677548

C 3.213088 0.573829 12.698855

H 2.674607 1.232499 13.388258

H 3.959056 0.018524 13.283048

H 3.748633 1.207336 11.983789

C 3.111864 -1.786395 10.720674

H 3.820602 -2.330330 11.360703

H 2.515720 -2.536044 10.187265

H 3.694536 -1.227921 9.980409

C -1.027533 -0.242983 6.071289

C -2.043863 -0.997604 6.943523

C -1.236080 -1.296316 8.203314

O -0.291639 -0.188416 8.327376

C -0.278258 0.603270 7.095335

H -0.344003 -0.944998 5.581506

H -1.495638 0.370494 5.297506

H -2.422410 -1.908604 6.472862

H -2.899037 -0.355019 7.179606

H -1.829474 -1.333853 9.118929

H -0.656786 -2.222089 8.111005

H 0.761989 0.805049 6.833357

H -0.788882 1.550873 7.299106

Si 2.708080 2.701035 4.602592

C 4.305779 1.687076 4.694763

H 4.551879 1.429394 5.729878

H 4.224920 0.756834 4.122738

H 5.148476 2.260816 4.283365

C 2.278341 3.107815 2.800375

H 2.180552 2.198815 2.197661

23

H 1.336933 3.662620 2.728687

H 3.065690 3.726561 2.346657

C 2.850023 4.278944 5.637750

H 1.930493 4.871917 5.593173

H 3.052241 4.044050 6.687581

H 3.672206 4.907613 5.267017

--------------------------------------------------------

24

Supplementary Table S13 | Cartesian coordinate of TS between II-SiMe3 and III in the quartet state. Units are presented in Å.



Imaginary frequency: 123i

--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe 0.634699 0.039720 9.550183

Si 2.104530 -0.541020 11.327280

Si -0.829145 1.162011 11.084188

N 1.917793 0.802776 8.450685

N 2.790819 1.190335 7.823344

C -2.042120 0.065218 12.072646

H -2.596124 -0.621476 11.421782

H -1.525110 -0.538340 12.825128

H -2.780784 0.689187 12.593806

C -1.925832 2.188040 9.883879

H -2.481670 1.549086 9.187465

H -2.661998 2.770060 10.455696

H -1.332700 2.893819 9.291654

C -0.101872 2.419790 12.315998

H -0.910208 2.986592 12.797158

H 0.479666 1.933893 13.105898

H 0.556256 3.135209 11.811189

C 1.431036 -1.248063 12.964945

H 0.909667 -0.495298 13.565210

H 0.732626 -2.073738 12.787682

H 2.260150 -1.637929 13.570898

C 3.366493 0.811770 11.767905

H 2.893922 1.659530 12.274692

H 4.138528 0.409931 12.437672

H 3.863965 1.194579 10.870610

C 3.071436 -1.985670 10.513718

H 3.822149 -2.367056 11.220031

H 2.418378 -2.825280 10.248257

H 3.596925 -1.665853 9.607720

C -1.512584 -1.487867 5.984546

C -2.451499 -1.956364 7.108406

C -1.531396 -1.948157 8.326012

O -0.574343 -0.873439 8.077229

C -0.663746 -0.431177 6.685670

H -0.886030 -2.316798 5.637691

H -2.045996 -1.079854 5.122171

H -2.883419 -2.943546 6.925285

H -3.272300 -1.243786 7.243890

H -2.038700 -1.734781 9.269075

H -0.969179 -2.883905 8.423078

H 0.353399 -0.339517 6.300377

H -1.142842 0.553902 6.675514

Si 2.935333 3.102634 6.121235

C 3.988694 2.066516 4.937660

H 4.608917 1.358135 5.496181

H 3.367392 1.494513 4.239739

H 4.655678 2.705781 4.343167

C 1.773980 4.241798 5.129332

25

H 1.122789 3.666957 4.462176

H 1.136391 4.837361 5.791229

H 2.356046 4.939330 4.509221

C 4.044664 4.141368 7.248362

H 3.453873 4.764212 7.928416

H 4.693517 3.501792 7.855161

H 4.684778 4.808076 6.654288

--------------------------------------------------------

26

Supplementary Table S14 | Cartesian coordinate of III in the quartet state. Units are presented in Å.



--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe -0.294114 -0.417058 0.235675

Si 1.289653 -1.684469 1.639215

Si -1.557397 1.237044 1.578419

N 0.800427 0.337256 -0.889973

N 1.712767 0.835497 -1.497041

C -3.032932 0.449554 2.517179

H -3.790483 0.060875 1.825411

H -2.711815 -0.377949 3.159855

H -3.527631 1.194867 3.155437

C -2.324865 2.662101 0.552131

H -2.998988 2.282451 -0.224782

H -2.904353 3.340872 1.193299

H -1.550203 3.256580 0.053849

C -0.479415 2.078122 2.913994

H -1.066336 2.819009 3.473968

H -0.088859 1.349886 3.633406

H 0.380201 2.595353 2.472992

C 0.504289 -2.522381 3.169287

H 0.031685 -1.787226 3.830328

H -0.263983 -3.251007 2.884421

H 1.266290 -3.056209 3.754000

C 2.671499 -0.541715 2.287158

H 2.270266 0.245701 2.934570

H 3.409651 -1.110792 2.868439

H 3.198469 -0.054377 1.458785

C 2.149827 -3.078703 0.649693

H 2.870285 -3.617248 1.280798

H 1.429256 -3.813088 0.270116

H 2.695258 -2.672846 -0.209734

C -2.291758 -3.130164 -2.668419

C -3.330669 -3.119107 -1.534386

C -2.509543 -2.625063 -0.348032

O -1.541843 -1.700394 -0.923736

C -1.454803 -1.886469 -2.368629

H -1.673115 -4.032173 -2.610271

H -2.742500 -3.091405 -3.663437

H -3.773864 -4.100955 -1.349335

H -4.139469 -2.415123 -1.758777

H -3.083327 -2.078504 0.403015

H -1.959433 -3.438464 0.139425

H -0.398975 -1.985158 -2.629375

H -1.861269 -0.986672 -2.842958

Si 1.892900 2.486728 -2.203353

C 3.328557 2.335273 -3.399076

H 4.232770 1.996875 -2.882233

H 3.106775 1.613769 -4.192753

H 3.549819 3.298935 -3.872298

C 0.296294 2.960831 -3.078977

H 0.083856 2.280645 -3.910966

27

H -0.554914 2.933158 -2.390489

H 0.364805 3.976401 -3.486949

C 2.280735 3.654275 -0.783269

H 1.458284 3.682390 -0.060768

H 3.185837 3.341351 -0.252555

H 2.440846 4.674464 -1.152311

--------------------------------------------------------

28

Supplementary Table S15 | Cartesian coordinate of III-SiMe3 in the quintet state. Units are presented in Å.



--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe 0.993234 0.603494 9.390072

Si 2.178828 -0.840627 11.002481

Si -0.534265 2.124877 10.606824

N 2.299825 1.452564 8.611283

N 3.312335 1.999105 8.251345

C -2.141630 1.235524 11.154861

H -2.716645 0.872240 10.294363

H -1.928539 0.375012 11.799034

H -2.790548 1.921470 11.716889

C -1.116307 3.634256 9.580165

H -1.608782 3.327777 8.649758

H -1.831396 4.244140 10.149630

H -0.271507 4.278224 9.309924

C 0.238024 2.842109 12.200878

H -0.470673 3.511110 12.708061

H 0.510383 2.049341 12.906409

H 1.146374 3.416945 11.987189

C 1.059726 -1.599157 12.356043

H 0.540784 -0.823504 12.930216

H 0.295759 -2.260005 11.929588

H 1.655088 -2.194311 13.062188

C 3.530347 0.154943 11.907232

H 3.101467 0.991220 12.470470

H 4.078741 -0.480745 12.615503

H 4.253110 0.569593 11.195373

C 3.058139 -2.316453 10.157678

H 3.598896 -2.921076 10.899090

H 2.346326 -2.976625 9.647873

H 3.783409 -1.969876 9.413405

C -0.739491 -1.201857 5.700182

C -1.148551 -2.217569 6.780102

C -1.111419 -1.371394 8.047859

O -0.023899 -0.426765 7.833022

C 0.318128 -0.359465 6.413229

H -0.342216 -1.673404 4.797769

H -1.597732 -0.584405 5.413292

H -0.416144 -3.029629 6.842129

H -2.134244 -2.656718 6.605541

H -2.038841 -0.804655 8.192080

H -0.888875 -1.931287 8.958461

H 1.326809 -0.768424 6.290763

H 0.318330 0.693133 6.120798

Si 3.589249 3.730820 7.814039

C 3.583883 4.722978 9.409528

H 4.335419 4.345498 10.110659

H 3.807732 5.777787 9.209533

H 2.607503 4.674068 9.902626

C 2.224018 4.286919 6.643985

H 1.237449 4.151341 7.100108

29

H 2.334276 5.348645 6.392987

H 2.247822 3.718792 5.707627

C 5.271547 3.751161 6.987018

H 5.553442 4.770362 6.698091

H 6.043471 3.366638 7.662004

H 5.278381 3.132503 6.083242

Si 4.294625 -1.373276 4.792588

C 4.466954 0.147683 3.672049

H 5.523231 0.325216 3.424113

H 3.921274 0.018190 2.731477

H 4.084418 1.048489 4.163036

C 5.220907 -1.117831 6.421534

H 6.292514 -0.963786 6.229359

H 4.846176 -0.244442 6.965878

H 5.121235 -1.990009 7.075826

C 4.907869 -2.925928 3.893762

H 5.973435 -2.828688 3.641218

H 4.794040 -3.818937 4.516972

H 4.358294 -3.093151 2.961539

--------------------------------------------------------

30

Supplementary Table S16 | Cartesian coordinate of TS between III-SiMe3 and IV in the quintet state. Units are presented in Å.




--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe 1.061362 0.385560 9.121851

Si 2.315033 -1.158830 10.595019

Si -0.300337 1.911587 10.532220

N 2.287909 1.225535 8.191560

N 3.237368 1.788488 7.706922

C -1.869986 1.025147 11.185851

H -2.525768 0.713098 10.363710

H -1.622345 0.132511 11.771099

H -2.451449 1.697863 11.831495

C -0.960558 3.468703 9.629752

H -1.573829 3.199139 8.761458

H -1.585702 4.072862 10.301983

H -0.146067 4.107303 9.270013

C 0.630240 2.538719 12.077509

H -0.013230 3.197830 12.676053

H 0.942047 1.706129 12.717705

H 1.531669 3.101807 11.811189

C 1.245258 -1.945509 11.974462

H 0.783564 -1.185349 12.614502

H 0.437651 -2.561359 11.561017

H 1.858947 -2.592969 12.615950

C 3.731669 -0.230898 11.476647

H 3.348713 0.576103 12.111231

H 4.309652 -0.913148 12.114732

H 4.421004 0.217755 10.752155

C 3.125598 -2.631901 9.677164

H 3.651345 -3.283627 10.388859

H 2.383955 -3.246001 9.152547

H 3.855170 -2.290054 8.935092

C -1.584725 -0.867126 5.771976

C -1.686812 -2.109110 6.673353

C -1.207750 -1.575932 8.020248

O -0.225028 -0.549052 7.691986

C -0.310256 -0.195297 6.278066

H -1.524665 -1.113161 4.708655

H -2.450671 -0.213413 5.922545

H -1.018256 -2.899311 6.314991

H -2.699227 -2.517269 6.729136

H -2.015523 -1.105726 8.592218

H -0.713491 -2.322473 8.645581

H 0.587778 -0.578440 5.783537

H -0.322777 0.894548 6.207534

Si 3.437928 3.569513 7.415101

C 3.274201 4.421713 9.081373

H 4.064080 4.100120 9.768233

H 3.347294 5.510051 8.969137

H 2.309868 4.194463 9.546102

C 2.089601 4.110323 6.219829

31

H 1.096042 3.911027 6.635803

H 2.157781 5.185678 6.016235

H 2.175903 3.581305 5.264704

C 5.148696 3.795835 6.689964

H 5.353291 4.860306 6.524240

H 5.918145 3.406088 7.364578

H 5.243631 3.276613 5.731314

Si 4.906718 -0.012322 5.656103

C 5.849791 -0.101150 4.005124

H 6.318516 -1.088322 3.881459

H 5.183225 0.060908 3.151291

H 6.644383 0.651212 3.957464

C 6.112424 -0.281172 7.091320

H 6.583180 -1.271924 7.021632

H 6.911523 0.467944 7.085258

H 5.595969 -0.215523 8.053430

C 3.544940 -1.332063 5.677186

H 3.981590 -2.340653 5.675479

H 2.923765 -1.238775 6.573511

H 2.901563 -1.245757 4.794407

--------------------------------------------------------

32

Supplementary Table S17 | Cartesian coordinate of IV in the quintet state. Units are presented in Å.



--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe -0.780883 -1.630526 -0.148185

Si -0.171575 0.230997 1.374778

C 1.454557 -0.137175 2.321961

H 1.366563 -1.025554 2.958604

H 2.295593 -0.296092 1.636764

H 1.714893 0.708503 2.973487

C -1.473903 0.612812 2.717110

H -1.618178 -0.241307 3.388625

H -1.164303 1.470396 3.329862

H -2.445380 0.850263 2.270192

C 0.138463 1.865647 0.439199

H 0.406717 2.660369 1.148678

H 0.958743 1.770275 -0.280317

H -0.748888 2.197115 -0.110134

Si 0.340683 -1.327746 -2.362509

C 2.249249 -1.227262 -2.209431

H 2.558020 -0.396894 -1.564233

H 2.671149 -2.147004 -1.785683

H 2.713423 -1.074961 -3.193752

C -0.191906 0.271599 -3.259898

H 0.012975 1.158861 -2.651292

H 0.352081 0.382136 -4.207889

H -1.263392 0.269316 -3.488413

C 0.012403 -2.759670 -3.596792

H 0.499015 -2.559112 -4.561487

H 0.405765 -3.714238 -3.225563

H -1.058878 -2.894261 -3.784569

N -2.521369 -1.614428 -0.147284

N -3.837214 -1.563435 0.020977

Si -4.508525 -2.853649 1.101419

Si -4.615331 -0.392878 -1.125513

C -3.828307 1.294560 -0.889149

H -2.753837 1.254360 -1.084961

H -4.272159 2.018676 -1.582813

H -3.976705 1.669468 0.129175

C -6.473653 -0.277205 -0.818756

H -6.719158 0.079215 0.186016

H -6.889222 0.444137 -1.533737

H -6.992265 -1.227187 -0.984490

C -4.327404 -1.040268 -2.869462

H -4.677223 -0.321205 -3.619655

H -3.263064 -1.222403 -3.044323

H -4.863524 -1.982060 -3.032907

C -4.780191 -4.412105 0.070090

H -5.583085 -4.270424 -0.662300

H -3.873048 -4.680146 -0.482147

H -5.056677 -5.264191 0.703021

C -6.140129 -2.317397 1.879672

H -6.959459 -2.236149 1.161202

33

H -6.431207 -3.067698 2.625557

H -6.045515 -1.358721 2.400818

C -3.266730 -3.166876 2.475887

H -3.644630 -3.951223 3.143202

H -2.292157 -3.476969 2.090527

H -3.114949 -2.261223 3.072774

C 0.561211 -5.886099 0.210392

C 1.811936 -5.019244 0.429355

C 1.235022 -3.806577 1.150105

O -0.090619 -3.620436 0.574610

C -0.522989 -4.848091 -0.089046

H 0.673985 -6.605204 -0.605134

H 0.320248 -6.443196 1.122393

H 2.247640 -4.719650 -0.529787

H 2.585555 -5.521644 1.016067

H 1.120311 -3.986873 2.226091

H 1.794207 -2.880963 1.001201

H -0.610827 -4.631613 -1.158215

H -1.506216 -5.117702 0.304190

--------------------------------------------------------

34

Supplementary Table S18 | Cartesian coordinate of IV in the triplet state. Units are presented in Å.



--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe -0.836668 -1.757874 -0.095339

Si 0.189795 -0.352418 1.586574

C 1.912135 0.471429 1.448073

H 2.710858 -0.266459 1.308260

H 1.978021 1.188053 0.623673

H 2.128760 1.015007 2.377905

C 0.363995 -1.433348 3.171739

H 1.145684 -2.194893 3.056809

H 0.647792 -0.805195 4.027615

H -0.563648 -1.953331 3.433725

C -1.007907 1.067086 2.046375

H -0.614724 1.638813 2.897941

H -1.143138 1.761323 1.210140

H -1.997443 0.689934 2.326746

Si 0.207632 -0.514709 -1.858652

C 2.095083 -0.838641 -1.943011

H 2.626134 -0.543790 -1.034699

H 2.309555 -1.896947 -2.133845

H 2.520406 -0.268887 -2.780777

C -0.022941 1.381841 -1.892510

H 0.422377 1.871369 -1.020530

H 0.449471 1.803995 -2.789852

H -1.083092 1.658851 -1.917347

C -0.388236 -1.111784 -3.582816

H 0.202424 -0.619467 -4.368334

H -0.254918 -2.193859 -3.699548

H -1.441629 -0.884725 -3.771373

N -2.542163 -1.995363 -0.273845

N -3.860975 -1.873294 -0.324271

Si -4.767104 -1.816943 1.252903

Si -4.506046 -1.648604 -2.008965

C -4.029200 0.075718 -2.585740

H -2.964942 0.264942 -2.426931

H -4.242204 0.209870 -3.652902

H -4.592315 0.837187 -2.034233

C -6.389595 -1.786747 -2.025668

H -6.884665 -1.060100 -1.373091

H -6.732218 -1.582750 -3.048167

H -6.740991 -2.787611 -1.758137

C -3.784569 -3.007456 -3.087344

H -4.074146 -2.864828 -4.135089

H -2.693354 -3.012422 -3.033781

H -4.152280 -3.989644 -2.768616

C -6.214707 -3.028627 1.212207

H -7.025056 -2.716435 0.549118

H -5.888445 -4.028736 0.905360

H -6.632976 -3.115560 2.222832

C -5.397402 -0.061449 1.527480

H -6.074562 0.261433 0.729219

35

H -5.947497 0.008997 2.473825

H -4.566198 0.650608 1.569259

C -3.606532 -2.331217 2.631940

H -4.148683 -2.307490 3.585424

H -3.234110 -3.349681 2.481377

H -2.743704 -1.667526 2.711732

C 0.394868 -6.037762 -0.014717

C 1.600731 -5.398624 0.694138

C 1.519196 -3.949907 0.224043

O 0.095687 -3.682188 0.072818

C -0.656928 -4.931682 0.058216

H 0.641975 -6.265515 -1.057399

H 0.055091 -6.960375 0.463142

H 2.552614 -5.865452 0.427978

H 1.482988 -5.456315 1.781768

H 1.918488 -3.222229 0.932883

H 2.002413 -3.804808 -0.748483

H -1.337311 -4.901907 -0.795343

H -1.243217 -4.979111 0.982298

--------------------------------------------------------

36

Supplementary Table S19 | Cartesian coordinate of IV-SiMe3 in the quartet state. Units are presented in Å.



--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe -0.536074 -1.304717 -0.014597

Si 0.336457 0.230548 1.638147

C 1.970083 1.218908 1.494119

H 2.839187 0.560194 1.380968

H 1.973598 1.917596 0.651686

H 2.121104 1.804425 2.411349

C 0.592314 -0.782462 3.255427

H 1.456782 -1.453497 3.177883

H 0.783584 -0.105030 4.099369

H -0.278223 -1.395795 3.510979

C -1.003850 1.535549 2.042440

H -0.694760 2.150023 2.898991

H -1.176282 2.206118 1.193906

H -1.963062 1.070319 2.294368

Si 0.403554 -0.005474 -1.791835

C 2.311688 -0.187919 -1.861543

H 2.812304 0.138863 -0.946571

H 2.603186 -1.227114 -2.056283

H 2.702580 0.415770 -2.692341

C 0.027198 1.866395 -1.854378

H 0.434427 2.399145 -0.989355

H 0.466074 2.310816 -2.757936

H -1.051097 2.061384 -1.880777

C -0.135301 -0.671109 -3.509300

H 0.423533 -0.150585 -4.299835

H 0.075668 -1.742625 -3.606334

H -1.201134 -0.523612 -3.706737

N -2.210414 -1.706345 -0.199436

N -3.533414 -1.725311 -0.259658

Si -4.458770 -1.787744 1.306549

Si -4.190512 -1.580091 -1.947591

C -3.888268 0.179340 -2.537575

H -2.842731 0.467754 -2.404936

H -4.136579 0.286641 -3.600238

H -4.507390 0.888151 -1.975928

C -6.050784 -1.906805 -1.960093

H -6.610948 -1.251439 -1.285341

H -6.421284 -1.712850 -2.974692

H -6.295629 -2.944758 -1.715979

C -3.337866 -2.864375 -3.020987

H -3.673605 -2.779232 -4.061393

H -2.253133 -2.736283 -3.003832

H -3.573960 -3.876430 -2.672980

C -5.704693 -3.206435 1.258200

H -6.545884 -3.017677 0.586205

H -5.228365 -4.144709 0.951450

H -6.115911 -3.357195 2.264293

C -5.354305 -0.145583 1.549377

H -6.064780 0.060639 0.741493

37

H -5.918437 -0.148904 2.490118

H -4.641697 0.685357 1.589413

C -3.254262 -2.094592 2.708950

H -3.811921 -2.157944 3.651639

H -2.711718 -3.035409 2.573159

H -2.518071 -1.293551 2.800128

C 1.019381 -5.468394 -0.038425

C 2.147677 -4.790363 0.756307

C 1.976290 -3.324097 0.371178

O 0.543650 -3.151117 0.171505

C -0.113719 -4.448948 0.062463

H 1.318998 -5.607948 -1.082912

H 0.733717 -6.442815 0.366534

H 3.141031 -5.169537 0.502557

H 1.994091 -4.924572 1.832655

H 2.292257 -2.617521 1.141175

H 2.487059 -3.083385 -0.567667

H -0.770965 -4.417404 -0.808588

H -0.720392 -4.593332 0.963081

Si -5.115003 -7.732417 -1.102437

C -4.702990 -8.717472 0.464605

H -5.125477 -8.243600 1.356733

H -5.114356 -9.734918 0.399553

H -3.621234 -8.804375 0.610391

C -6.992170 -7.589383 -1.319324

H -7.456919 -7.094594 -0.460275

H -7.248983 -7.017110 -2.216740

H -7.445147 -8.586302 -1.417236

C -4.327441 -8.542560 -2.624491

H -4.541180 -7.973117 -3.534922

H -3.239680 -8.614556 -2.521707

H -4.718373 -9.560263 -2.766095

--------------------------------------------------------

38

Supplementary Table S20 | Cartesian coordinate of TS between IV-SiMe3 and V in the quartet state. Units are presented in Å.




--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe -0.885252 -1.927095 -0.226947

Si 0.148311 -0.494436 1.470431

C 1.904137 0.248217 1.289085

H 2.664669 -0.523964 1.123015

H 1.978501 0.965547 0.466039

H 2.172006 0.776361 2.214465

C 0.298711 -1.537446 3.082537

H 1.022854 -2.353673 2.970910

H 0.649734 -0.900901 3.906649

H -0.654872 -1.978701 3.393497

C -0.974448 0.981200 1.938226

H -0.497350 1.586256 2.721221

H -1.169626 1.635283 1.082417

H -1.940447 0.641860 2.327407

Si 0.068394 -0.588027 -2.002504

C 1.954301 -0.871317 -2.195927

H 2.521173 -0.636919 -1.291270

H 2.173997 -1.906873 -2.480067

H 2.331308 -0.226934 -3.002099

C -0.174751 1.307528 -1.917882

H 0.357665 1.760924 -1.075595

H 0.202535 1.772582 -2.838842

H -1.232168 1.578720 -1.820627

C -0.605731 -1.073437 -3.730173

H -0.035180 -0.543914 -4.506174

H -0.502392 -2.148302 -3.916879

H -1.660233 -0.812410 -3.859736

N -2.556051 -2.471415 -0.434436

N -3.883893 -2.667725 -0.477950

Si -4.660505 -2.367658 1.174003

Si -4.595724 -1.957659 -2.031277

C -4.164374 -0.129340 -2.099662

H -3.086284 0.030537 -2.030539

H -4.508113 0.285888 -3.055194

H -4.644860 0.440351 -1.299149

C -6.478616 -2.116023 -2.032922

H -6.958899 -1.420164 -1.338076

H -6.828908 -1.855276 -3.040057

H -6.835090 -3.125643 -1.814455

C -3.890974 -2.835463 -3.533966

H -4.062098 -2.207156 -4.416506

H -2.814439 -2.987574 -3.440826

H -4.370412 -3.800132 -3.719948

C -6.410941 -3.069682 1.297674

H -7.119922 -2.568691 0.634610

H -6.469726 -4.144773 1.108798

H -6.756026 -2.901424 2.326624

C -4.760917 -0.505253 1.440086

39

H -5.544062 -0.039124 0.833172

H -4.998067 -0.299007 2.490976

H -3.810853 -0.015606 1.210233

C -3.582234 -3.128729 2.505617

H -3.989258 -2.853007 3.486243

H -3.554023 -4.219035 2.451256

H -2.560880 -2.749076 2.439737

C 1.028099 -5.859915 1.002410

C 2.269793 -4.973791 0.815928

C 1.767292 -3.902514 -0.152001

O 0.339763 -3.777987 0.105814

C -0.101375 -4.833458 1.003542

H 0.918480 -6.550015 0.158325

H 1.053418 -6.448136 1.923764

H 3.131613 -5.515830 0.417824

H 2.563065 -4.522374 1.769944

H 2.225044 -2.922493 -0.005081

H 1.895345 -4.201199 -1.198661

H -1.050862 -5.212889 0.623696

H -0.258260 -4.401011 1.998646

Si -4.318439 -5.216754 -0.870548

C -4.278283 -6.244314 0.732326

H -5.143326 -6.080546 1.381727

H -4.276059 -7.307101 0.450347

H -3.373406 -6.062071 1.319292

C -5.795066 -5.852818 -1.890931

H -6.736271 -5.737118 -1.342680

H -5.900318 -5.341099 -2.851805

H -5.662849 -6.924513 -2.096942

C -2.676486 -5.462296 -1.762182

H -2.807613 -5.528926 -2.845684

H -2.011594 -4.612598 -1.551666

H -2.183074 -6.380266 -1.420604

--------------------------------------------------------

40

Supplementary Table S21 | Cartesian coordinate of V in the quartet state. Units are presented in Å.



--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe 0.986199 0.422019 0.122292

Si 1.764917 2.257138 1.536158

C 3.598424 2.819150 1.519091

H 4.288549 1.994206 1.731453

H 3.888749 3.250377 0.555522

H 3.758663 3.587065 2.288319

C 1.468190 1.744929 3.369083

H 2.034613 0.847935 3.646573

H 1.780020 2.553771 4.044736

H 0.410732 1.536394 3.566961

C 0.772824 3.882615 1.327351

H 1.126180 4.626638 2.054299

H 0.895152 4.309159 0.326840

H -0.300179 3.742798 1.498183

Si 2.225315 1.260481 -1.788832

C 4.096209 0.846911 -1.679053

H 4.582165 1.309172 -0.814465

H 4.266666 -0.235313 -1.629591

H 4.604756 1.214579 -2.581156

C 2.148949 3.127366 -2.211541

H 2.601029 3.749905 -1.432385

H 2.689202 3.322179 -3.148144

H 1.117540 3.472587 -2.348915

C 1.690840 0.411441 -3.426662

H 2.362604 0.713444 -4.242550

H 1.724848 -0.681689 -3.355062

H 0.674576 0.696742 -3.718621

N -0.548087 -0.460360 -0.036131

N -2.034183 -0.602160 -0.163014

Si -2.581486 -0.351810 1.622856

Si -2.676183 0.689420 -1.383025

C -1.851695 2.352530 -1.146318

H -0.763210 2.263030 -1.159092

H -2.149448 2.979723 -1.996739

H -2.145741 2.871247 -0.233442

C -4.548159 0.884075 -1.187456

H -4.839379 1.342429 -0.238057

H -4.891381 1.555038 -1.985610

H -5.095946 -0.056002 -1.297720

C -2.348007 0.131737 -3.149235

H -2.638739 0.968246 -3.797606

H -1.293573 -0.076475 -3.336590

H -2.936677 -0.735250 -3.458871

C -4.328324 -1.050909 1.840680

H -5.053640 -0.647755 1.129484

H -4.359143 -2.142884 1.778128

H -4.672780 -0.779803 2.847027

C -2.620022 1.480960 2.031093

H -3.397206 2.043341 1.507633

41

H -2.830049 1.559684 3.105191

H -1.652397 1.952204 1.849476

C -1.463288 -1.182613 2.880590

H -1.826681 -0.875191 3.870691

H -1.485402 -2.272220 2.847724

H -0.431210 -0.846825 2.774356

C 3.424477 -3.232737 0.522192

C 4.262366 -2.459770 1.554047

C 3.635923 -1.059119 1.524820

O 2.282665 -1.230221 1.011811

C 2.040336 -2.630061 0.733843

H 3.775205 -3.027032 -0.495038

H 3.440283 -4.314979 0.679462

H 5.328087 -2.435062 1.311856

H 4.152830 -2.912547 2.545655

H 3.575151 -0.594999 2.513005

H 4.161816 -0.383134 0.847223

H 1.376249 -2.676473 -0.129367

H 1.535987 -3.082779 1.599213

Si -2.144685 -2.369969 -0.791637

C -1.758229 -3.609121 0.571701

H -2.507901 -3.641949 1.366238

H -1.756278 -4.596287 0.091022

H -0.774812 -3.451378 1.016590

C -3.917002 -2.745404 -1.353117

H -4.655319 -2.624489 -0.555023

H -4.241921 -2.149345 -2.210402

H -3.947354 -3.797519 -1.665812

C -0.961202 -2.654668 -2.225070

H -1.469599 -2.653584 -3.193198

H -0.171898 -1.901660 -2.229962

H -0.491111 -3.637066 -2.097938

--------------------------------------------------------

42

Supplementary Table S22 | Cartesian coordinate of TS between V and VI in the quartet state. Units are presented in Å.




--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe 1.118373 0.391617 0.069673

Si 1.729424 2.217845 1.583698

C 3.556403 2.797949 1.522497

H 4.265833 1.982178 1.701607

H 3.812196 3.250362 0.558715

H 3.724993 3.555811 2.300025

C 1.466439 1.692088 3.411492

H 2.050334 0.800862 3.671706

H 1.777073 2.498878 4.089760

H 0.415641 1.465198 3.622009

C 0.718355 3.826379 1.369466

H 1.081030 4.581818 2.079716

H 0.819430 4.240558 0.361372

H -0.349180 3.679835 1.562740

Si 2.273678 1.266895 -1.906175

C 4.164286 0.966708 -1.796949

H 4.609551 1.415369 -0.903760

H 4.396640 -0.105043 -1.794712

H 4.659810 1.405357 -2.673964

C 2.062010 3.131709 -2.271062

H 2.462177 3.759861 -1.468261

H 2.597170 3.390621 -3.194909

H 1.010475 3.405816 -2.411610

C 1.775386 0.394005 -3.537686

H 2.423385 0.731037 -4.358726

H 1.870541 -0.695538 -3.466138

H 0.742256 0.619011 -3.822953

N -0.323493 -0.522344 0.085842

N -2.138733 -0.591444 -0.125797

Si -2.653810 -0.349803 1.630295

Si -2.668887 0.695282 -1.333109

C -1.821172 2.350557 -1.082557

H -0.733677 2.250669 -1.063179

H -2.084896 2.983781 -1.939534

H -2.132108 2.874608 -0.177986

C -4.541716 0.950002 -1.204267

H -4.857688 1.379160 -0.249023

H -4.843897 1.654320 -1.989990

H -5.102334 0.023515 -1.362017

C -2.320635 0.157641 -3.105361

H -2.627709 0.991856 -3.749085

H -1.261896 -0.029163 -3.293143

H -2.887831 -0.720120 -3.425148

C -4.396156 -1.057839 1.858460

H -5.120714 -0.644347 1.151223

H -4.425798 -2.148649 1.774116

H -4.741098 -0.805143 2.869309

C -2.725024 1.481906 2.060380

43

H -3.477270 2.047187 1.504471

H -2.990211 1.548576 3.122985

H -1.754970 1.965937 1.931591

C -1.536805 -1.154970 2.911896

H -1.896345 -0.829477 3.897340

H -1.560294 -2.245355 2.898077

H -0.504185 -0.825127 2.792902

C 3.411953 -3.356957 0.651304

C 4.259732 -2.497452 1.603193

C 3.751525 -1.075949 1.332656

O 2.410980 -1.229754 0.773653

C 2.068876 -2.639346 0.690469

H 3.824825 -3.335959 -0.363272

H 3.336467 -4.400473 0.969380

H 5.334081 -2.586925 1.422829

H 4.067624 -2.783507 2.642905

H 3.680269 -0.467496 2.237499

H 4.355110 -0.546697 0.591769

H 1.447397 -2.768952 -0.194803

H 1.486958 -2.912634 1.579513

Si -2.134229 -2.325280 -0.749627

C -1.770063 -3.583122 0.607362

H -2.534829 -3.623370 1.387432

H -1.757049 -4.566964 0.120275

H -0.797662 -3.423749 1.075514

C -3.879397 -2.752407 -1.364286

H -4.634220 -2.670151 -0.576325

H -4.207935 -2.138686 -2.208252

H -3.876859 -3.795361 -1.707382

C -0.928559 -2.617170 -2.172557

H -1.438083 -2.663433 -3.139613

H -0.156618 -1.848742 -2.213062

H -0.434891 -3.583815 -2.014812

--------------------------------------------------------

44

Supplementary Table S23 | Cartesian coordinate of VI-N(SiMe3)3 in the quartet state. Units are presented in Å.



--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe 3.256879 0.030510 -0.377115

Si 3.744991 2.975019 0.397684

C 5.185114 4.149109 -0.000010

H 6.117747 3.591551 -0.144997

H 5.008454 4.740893 -0.905001

H 5.343273 4.854509 0.825511

C 4.193834 2.128134 2.037447

H 5.089270 1.503971 1.935947

H 4.399250 2.883844 2.807531

H 3.379230 1.493656 2.405794

C 2.208099 4.034421 0.736107

H 2.382533 4.731517 1.565552

H 1.921580 4.624775 -0.140777

H 1.352791 3.402554 1.002547

Si 3.445043 2.156059 -2.590489

C 5.188960 2.143395 -3.336868

H 5.830035 2.899389 -2.869599

H 5.666197 1.168025 -3.185888

H 5.165378 2.344227 -4.415554

C 2.664576 3.843588 -2.981353

H 3.202470 4.677104 -2.516819

H 2.668711 4.016966 -4.064882

H 1.623392 3.887911 -2.642216

C 2.418967 0.873438 -3.543159

H 2.380643 1.131983 -4.609748

H 2.844607 -0.133718 -3.462441

H 1.389047 0.834205 -3.170015

N 3.471344 1.817784 -0.878583

N -3.660255 -1.095182 -0.339798

Si -3.911792 -1.250878 1.416288

Si -3.866861 0.496023 -1.123886

C -2.682897 1.796528 -0.432011

H -1.659396 1.407777 -0.380545

H -2.668946 2.659404 -1.109314

H -2.954735 2.165810 0.558732

C -5.660876 1.082622 -0.966284

H -6.004369 1.160800 0.069516

H -5.780854 2.070555 -1.427729

H -6.335351 0.391093 -1.484760

C -3.496151 0.464268 -2.981148

H -3.797571 1.443580 -3.374392

H -2.428578 0.350307 -3.190212

H -4.042582 -0.291057 -3.552052

C -5.529425 -2.164099 1.786795

H -6.383853 -1.580961 1.423567

H -5.590009 -3.154507 1.325960

H -5.655162 -2.295264 2.868711

C -4.040105 0.409054 2.318571

H -4.777392 1.104692 1.910244

45

H -4.348741 0.180443 3.346796

H -3.077514 0.925060 2.377231

C -2.460000 -2.116951 2.272518

H -2.550854 -1.978030 3.356956

H -2.403741 -3.190699 2.082998

H -1.511658 -1.661933 1.962955

C 2.172329 -4.080891 0.347197

C 3.394142 -3.946286 1.269734

C 4.108217 -2.722136 0.703991

O 3.035301 -1.881380 0.161748

C 1.773867 -2.627988 0.105377

H 2.452580 -4.563464 -0.595090

H 1.358360 -4.655097 0.796292

H 4.036606 -4.830231 1.261235

H 3.077872 -3.762788 2.301997

H 4.648145 -2.132179 1.446394

H 4.781053 -2.973433 -0.122060

H 1.321672 -2.441402 -0.869992

H 1.121165 -2.236526 0.891937

Si -3.500522 -2.555680 -1.343380

C -3.205513 -4.133723 -0.333006

H -3.934321 -4.325809 0.458606

H -3.267833 -4.972062 -1.038700

H -2.205245 -4.158932 0.110133

C -5.075411 -2.869707 -2.345091

H -5.918109 -3.086068 -1.678247

H -5.362847 -2.020440 -2.972255

H -4.943336 -3.736587 -3.004348

C -2.001360 -2.475892 -2.498917

H -2.160219 -1.871815 -3.394592

H -1.128108 -2.070502 -1.974824

H -1.750067 -3.491529 -2.829274

--------------------------------------------------------

46

Supplementary Table S24 | Cartesian coordinate of VII in the quartet state. Units are presented in Å.



--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe 4.062061 1.277161 0.351975

Si 1.396582 2.139061 1.794823

C 2.646924 2.164947 3.221684

H 3.127924 1.191258 3.376597

H 3.438252 2.905652 3.061835

H 2.136165 2.425463 4.157671

C 0.074024 0.856070 2.253410

H 0.507136 -0.147800 2.339360

H -0.385719 1.100862 3.219203

H -0.726109 0.808365 1.507540

C 0.562342 3.840984 1.753486

H 0.108168 4.071986 2.725088

H 1.289503 4.629535 1.529089

H -0.232034 3.897405 1.000713

Si 1.501958 1.940360 -1.305823

C 2.394692 0.812486 -2.546842

H 3.458055 1.062343 -2.641999

H 2.320008 -0.244527 -2.263819

H 1.945891 0.916773 -3.542745

C 1.659087 3.716194 -1.944224

H 2.709371 4.026801 -1.983772

H 1.243142 3.811081 -2.955135

H 1.129209 4.424641 -1.297982

C -0.335057 1.465611 -1.370797

H -0.713288 1.582566 -2.394178

H -0.497387 0.422689 -1.075528

H -0.954563 2.095472 -0.722857

N 2.191927 1.745216 0.289342

C 3.666821 -3.130570 0.346292

C 5.174005 -3.019910 0.630118

C 5.487634 -1.590408 0.198699

O 4.259752 -0.837218 0.462483

C 3.153909 -1.753134 0.753596

H 3.488663 -3.307060 -0.719994

H 3.181717 -3.931466 0.910138

H 5.770064 -3.752743 0.080351

H 5.373750 -3.150854 1.699161

H 6.297776 -1.117798 0.756952

H 5.700032 -1.520643 -0.873521

H 2.283162 -1.403001 0.197849

H 2.943260 -1.692518 1.826832

Si 6.135134 2.684282 0.242567

C 6.319326 3.591265 -1.432376

H 5.456800 4.236270 -1.636091

H 7.216549 4.225215 -1.435243

H 6.406591 2.886698 -2.267744

C 6.146601 4.054528 1.577623

H 5.274276 4.711633 1.483474

H 6.136107 3.635383 2.590423

47

H 7.045391 4.679128 1.484474

C 7.777926 1.720595 0.483785

H 7.812897 1.216907 1.457557

H 7.919348 0.958757 -0.292570

H 8.638414 2.401938 0.435264

--------------------------------------------------------

48

Supplementary Table S25 | Cartesian coordinate of VII-SiMe3 in the quartet state. Units are presented in Å.



--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe 0.332258 0.351448 -0.446358

Si 1.698627 0.792910 2.348723

C 2.843854 -0.483520 1.536300

H 2.318671 -1.413000 1.284549

H 3.308165 -0.103445 0.619526

H 3.653077 -0.746874 2.229599

C 1.022222 -0.019661 3.926499

H 0.423110 -0.908028 3.691502

H 1.843249 -0.340755 4.579943

H 0.388632 0.663850 4.501070

C 2.779093 2.260094 2.872601

H 3.587725 1.928492 3.535833

H 3.238592 2.740859 2.001581

H 2.208205 3.024756 3.411393

Si 1.411986 0.827604 -2.661553

C 0.620862 -0.093863 -4.148861

H 0.715094 -1.182222 -4.050587

H -0.445867 0.140641 -4.248893

H 1.112231 0.194308 -5.088304

C 3.267294 0.356125 -2.707913

H 3.422153 -0.711376 -2.511829

H 3.700585 0.580384 -3.692269

H 3.842480 0.913785 -1.959637

C 1.340884 2.682712 -3.123132

H 1.840540 2.862029 -4.084939

H 0.308055 3.038947 -3.212511

H 1.838736 3.303184 -2.369201

N 0.419596 1.258943 1.253663

Si -0.641058 2.634671 1.455365

C -1.168100 2.893709 3.260696

H -1.687565 2.015977 3.661670

H -0.319812 3.109517 3.919901

H -1.856033 3.745869 3.328481

C -2.237268 2.379796 0.458195

H -2.783260 1.489339 0.792026

H -2.904407 3.241425 0.586168

H -2.041936 2.274964 -0.615643

C 0.158938 4.241251 0.851679

H 0.435686 4.167167 -0.206135

H -0.523139 5.093659 0.961740

H 1.070265 4.468326 1.416026

C -2.065479 -3.384071 -0.819571

C -1.991617 -3.194051 0.704682

C -1.771114 -1.692236 0.832253

O -0.945957 -1.341226 -0.323408

C -1.023582 -2.394721 -1.340682

H -1.847922 -4.407630 -1.135344

H -3.059795 -3.115498 -1.192719

H -1.141407 -3.742860 1.124391

49

H -2.898210 -3.521617 1.220309

H -2.710939 -1.133084 0.761491

H -1.230622 -1.376259 1.725481

H -0.027520 -2.840177 -1.427134

H -1.296057 -1.928063 -2.289415

Si -4.954331 -0.919685 -3.485245

C -4.494004 0.916556 -3.508699

H -3.503127 1.074042 -3.946816

H -5.219021 1.485631 -4.107920

H -4.486660 1.342558 -2.500238

C -4.891441 -1.653731 -5.230892

H -3.901543 -1.526163 -5.680912

H -5.124581 -2.723592 -5.225737

H -5.622031 -1.155246 -5.883752

C -6.665515 -1.175627 -2.710757

H -7.436169 -0.661912 -3.302890

H -6.931725 -2.236896 -2.667447

H -6.707009 -0.774889 -1.692590

--------------------------------------------------------

50

Supplementary Table S26 | Cartesian coordinate of TS between VII-SiMe3 and VIII in the quartet state. Units are presented in Å.




--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe -0.081300 0.213223 -0.609668

Si 1.445558 0.636468 2.113988

C 2.507417 -0.689694 1.268492

H 1.935992 -1.597287 1.038652

H 2.952540 -0.329193 0.334912

H 3.329202 -0.983058 1.934465

C 0.852141 -0.124286 3.751160

H 0.241487 -1.019553 3.580263

H 1.709069 -0.426507 4.366578

H 0.252262 0.577059 4.339901

C 2.595921 2.082726 2.537987

H 3.428277 1.742208 3.166432

H 3.022605 2.525865 1.631020

H 2.078617 2.878914 3.084922

Si 1.011629 0.720715 -2.808969

C 0.756172 -0.585649 -4.190502

H 1.133290 -1.571220 -3.892029

H -0.303439 -0.699481 -4.449117

H 1.291282 -0.291419 -5.103936

C 2.908842 0.884690 -2.612073

H 3.367967 -0.055321 -2.284653

H 3.373264 1.166492 -3.567024

H 3.170521 1.653826 -1.876244

C 0.438523 2.382683 -3.565783

H 0.974775 2.585886 -4.502851

H -0.634498 2.380926 -3.787753

H 0.631530 3.220822 -2.886233

N 0.113360 1.114260 1.088925

Si -0.905781 2.512266 1.346594

C -1.300667 2.811388 3.179058

H -1.806924 1.951287 3.631518

H -0.405015 3.022808 3.773485

H -1.966857 3.677746 3.277226

C -2.571256 2.276826 0.465865

H -3.112211 1.405109 0.853314

H -3.210025 3.155982 0.618083

H -2.447182 2.143814 -0.615633

C -0.123124 4.095684 0.662330

H 0.060382 4.007146 -0.414537

H -0.774725 4.964216 0.820577

H 0.838036 4.307429 1.143815

C -2.117324 -3.755063 -0.651084

C -1.991336 -3.486033 0.858001

C -1.876153 -1.967562 0.905291

O -1.127885 -1.619018 -0.300009

C -1.174345 -2.718886 -1.264340

H -1.840131 -4.774622 -0.930588

H -3.146443 -3.580478 -0.982966

51

H -1.084820 -3.951402 1.260017

H -2.847011 -3.852936 1.430943

H -2.857027 -1.480897 0.852962

H -1.323732 -1.569550 1.757174

H -0.154017 -3.097693 -1.380005

H -1.520255 -2.311824 -2.217412

Si -3.822291 -0.002238 -3.158488

C -3.907254 1.771301 -3.812484

H -3.105510 1.971742 -4.530145

H -4.865845 1.942598 -4.322761

H -3.824071 2.502256 -3.002116

C -3.946307 -1.240348 -4.591446

H -3.134437 -1.098572 -5.312162

H -3.906176 -2.276695 -4.239325

H -4.896411 -1.108881 -5.128870

C -5.208229 -0.311131 -1.899774

H -6.191495 -0.162871 -2.368574

H -5.179957 -1.333296 -1.507108

H -5.134152 0.379844 -1.053879

--------------------------------------------------------

52

Supplementary Table S27 | Cartesian coordinate of VIII in the quartet state. Units are presented in Å.



--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe 3.728728 2.480158 0.313528

Si 1.179854 2.292317 2.121988

C 2.119380 3.556389 3.175730

H 3.191088 3.350591 3.250820

H 2.001881 4.570901 2.780535

H 1.714791 3.549940 4.195909

C 1.310620 0.607163 2.989320

H 2.349269 0.260013 3.039870

H 0.929273 0.657489 4.016957

H 0.730810 -0.156608 2.458137

C -0.641254 2.823735 2.234491

H -0.936575 2.850080 3.291224

H -0.798303 3.827741 1.825233

H -1.328933 2.141461 1.724337

Si 0.786418 1.788140 -0.869149

C 1.781005 1.441735 -2.448556

H 2.452091 2.264126 -2.713701

H 2.375361 0.526739 -2.366817

H 1.084254 1.305451 -3.285143

C -0.447201 3.159729 -1.313805

H 0.060270 4.112229 -1.502712

H -1.000937 2.893320 -2.223015

H -1.179135 3.328854 -0.518580

C -0.223742 0.204587 -0.560911

H -0.829806 -0.035779 -1.443653

H 0.425997 -0.656882 -0.364131

H -0.908739 0.298023 0.288345

N 1.810215 2.199026 0.487406

C 4.384691 -1.651938 -1.327388

C 5.638569 -0.978652 -1.909683

C 5.303596 0.505135 -1.776389

O 4.465087 0.603398 -0.587648

C 4.019956 -0.722914 -0.171939

H 3.581638 -1.673890 -2.071596

H 4.563962 -2.675918 -0.989553

H 5.836920 -1.263052 -2.946348

H 6.521839 -1.229253 -1.311800

H 6.173627 1.146951 -1.626259

H 4.725283 0.871983 -2.631347

H 2.951586 -0.660396 0.042755

H 4.554401 -0.988590 0.747228

Si 5.811230 2.674688 1.647936

C 7.436302 2.197279 0.766912

H 7.724911 2.902135 -0.018219

H 8.251014 2.169844 1.502852

H 7.369409 1.198783 0.320879

C 6.184386 4.217816 2.698407

H 6.488208 5.079497 2.097052

H 5.321335 4.518961 3.300794

53

H 7.006904 3.989469 3.389201

C 5.515474 1.268420 2.919758

H 4.658357 1.460455 3.572828

H 5.361194 0.295885 2.440748

H 6.404952 1.180392 3.559116

Si 4.301606 4.703873 -0.508178

C 3.293790 4.914800 -2.116530

H 2.225391 4.742586 -1.963694

H 3.421969 5.946820 -2.471863

H 3.637240 4.247406 -2.913898

C 3.714922 6.089336 0.654879

H 2.637856 6.014774 0.836670

H 4.221561 6.081144 1.623436

H 3.906354 7.062451 0.182889

C 6.090218 5.098500 -1.036218

H 6.792846 5.156642 -0.200720

H 6.472665 4.358405 -1.747758

H 6.095958 6.073248 -1.542319

--------------------------------------------------------

54

Supplementary Table S28 | Cartesian coordinate of TS between VIII and IX in the quartet state. Units are presented in Å.




--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe 3.940037 2.242149 0.364184

Si 1.420899 2.898344 1.972427

C 2.469636 3.981309 3.112869

H 3.507411 3.642098 3.173255

H 2.473022 5.039890 2.840458

H 2.039994 3.908891 4.120609

C 1.428889 1.177433 2.766387

H 2.449577 0.780418 2.818957

H 1.049682 1.242325 3.794406

H 0.810000 0.451784 2.232108

C -0.346921 3.577299 2.048139

H -0.677528 3.585910 3.094352

H -0.398654 4.605922 1.677228

H -1.070626 2.980252 1.485316

Si 0.987927 2.206615 -1.008349

C 1.941190 1.515764 -2.488137

H 2.665122 2.210857 -2.918782

H 2.470822 0.600281 -2.213888

H 1.216416 1.265492 -3.273631

C -0.223966 3.494564 -1.686984

H 0.277479 4.292820 -2.243035

H -0.909480 2.994970 -2.383367

H -0.831509 3.958506 -0.904031

C -0.068325 0.749136 -0.404288

H -0.674446 0.399464 -1.250012

H 0.547062 -0.094526 -0.074609

H -0.758987 0.999097 0.405978

N 2.047608 2.852111 0.285432

C 4.294233 -2.241409 -0.757359

C 5.543251 -1.655361 -1.435822

C 5.174789 -0.179027 -1.606643

O 4.196715 0.115020 -0.566688

C 3.861904 -1.099223 0.157718

H 3.515447 -2.454355 -1.498092

H 4.499003 -3.161192 -0.202940

H 5.776977 -2.132697 -2.391049

H 6.414880 -1.760705 -0.781813

H 6.022406 0.499296 -1.481348

H 4.700571 0.019386 -2.574471

H 2.789025 -1.079590 0.364603

H 4.411351 -1.106581 1.106187

Si 6.233378 2.265547 1.364515

C 7.653953 2.788472 0.179349

H 7.545689 3.822722 -0.166564

H 8.625406 2.711319 0.686818

H 7.700004 2.153115 -0.713976

C 6.502228 3.319825 2.943296

H 6.331154 4.386686 2.769153

55

H 5.836077 3.005382 3.755766

H 7.533933 3.202389 3.302416

C 6.756793 0.501864 1.939665

H 6.071744 0.098207 2.695556

H 6.796496 -0.214155 1.110464

H 7.758045 0.533260 2.390959

Si 3.301243 4.636862 -0.240442

C 3.631107 4.640680 -2.114014

H 2.745550 4.402615 -2.708608

H 3.935781 5.662798 -2.377111

H 4.440782 3.967267 -2.409593

C 1.863412 5.860443 0.015126

H 0.926811 5.548819 -0.448615

H 1.666038 6.065668 1.071475

H 2.165512 6.813268 -0.440340

C 4.736900 5.606220 0.567962

H 4.664310 5.629409 1.658503

H 5.711221 5.190904 0.302161

H 4.687436 6.644818 0.209455

--------------------------------------------------------

56

Supplementary Table S29 | Cartesian coordinate of IX in the quartet state. Units are presented in Å.



--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe 0.917476 0.564365 0.157574

Si -1.940644 0.551579 1.470202

C -1.517969 1.466209 3.067252

H -0.448145 1.433093 3.291908

H -1.852936 2.505916 3.104239

H -2.037812 0.931247 3.873040

C -1.410574 -1.232793 1.770567

H -0.385638 -1.266233 2.156125

H -2.068043 -1.655348 2.543243

H -1.453965 -1.886858 0.898249

C -3.822944 0.650239 1.293242

H -4.273184 0.247434 2.209325

H -4.169395 1.683193 1.187480

H -4.224450 0.073441 0.456222

Si -1.712886 0.637223 -1.631291

C -0.372410 0.625522 -2.959821

H 0.094069 1.593800 -3.147229

H 0.421664 -0.088255 -2.719012

H -0.842589 0.295953 -3.896846

C -3.167399 1.678961 -2.250835

H -2.903500 2.715473 -2.478283

H -3.532841 1.226641 -3.181262

H -4.002116 1.689504 -1.543137

C -2.320760 -1.142860 -1.526233

H -2.712261 -1.381105 -2.524703

H -1.528268 -1.867198 -1.314309

H -3.136176 -1.308803 -0.818078

N -1.106185 1.278759 -0.004401

C 0.830084 -5.916996 -0.329445

C 1.823953 -4.776831 -0.054761

C 1.228639 -3.644082 -0.889431

O -0.199823 -3.817702 -0.816491

C -0.508603 -5.169863 -0.420706

H 1.065265 -6.402586 -1.283333

H 0.826267 -6.685812 0.448168

H 2.851004 -5.018446 -0.341636

H 1.819872 -4.508576 1.007734

H 1.465372 -2.642953 -0.516035

H 1.552874 -3.713452 -1.938955

H -1.192738 -5.607984 -1.156339

H -1.020094 -5.137233 0.550704

Si 3.324531 0.136750 0.431354

C 4.200895 -0.461057 -1.166553

H 4.088262 0.267888 -1.977779

H 5.276389 -0.606775 -0.994770

H 3.788465 -1.412156 -1.524006

C 4.283324 1.713856 0.958526

H 4.173039 2.516955 0.219989

H 3.926038 2.100344 1.920659

57

H 5.356897 1.504036 1.063349

C 3.759187 -1.169807 1.767178

H 3.373629 -0.877495 2.751088

H 3.334797 -2.152207 1.528767

H 4.847642 -1.290625 1.857550

Si -0.819944 3.102485 0.058025

C -0.156700 3.765609 -1.580763

H -0.817182 3.618520 -2.438473

H -0.029349 4.848104 -1.450698

H 0.825568 3.348511 -1.822165

C -2.443013 4.008918 0.421644

H -3.219634 3.806562 -0.321402

H -2.851981 3.774182 1.409064

H -2.244741 5.088051 0.405427

C 0.433645 3.652122 1.358321

H 0.141795 3.431116 2.385828

H 1.425330 3.223608 1.185718

H 0.523363 4.743918 1.269144

--------------------------------------------------------

58

Supplementary Table S30 | Cartesian coordinate of IX-SiMe3 in the quintet state. Units are presented in Å.



--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe 0.832847 0.452879 0.290545

Si -1.992463 0.452574 1.667632

C -1.544839 1.460384 3.200707

H -0.469698 1.449104 3.401700

H -1.888434 2.497755 3.186719

H -2.040607 0.967389 4.047388

C -1.424877 -1.303167 2.054173

H -0.370384 -1.310368 2.350682

H -2.012413 -1.666832 2.908638

H -1.544039 -2.016104 1.237223

C -3.880355 0.500691 1.534567

H -4.298608 0.122485 2.475971

H -4.254696 1.520081 1.397975

H -4.286338 -0.117702 0.729789

Si -1.834631 0.360272 -1.439264

C -0.525219 0.313328 -2.796751

H -0.090400 1.280196 -3.055122

H 0.293918 -0.363411 -2.533463

H -1.006974 -0.086734 -3.699977

C -3.341999 1.312851 -2.077857

H -3.127317 2.346713 -2.361755

H -3.706025 0.799908 -2.976909

H -4.163071 1.324667 -1.354287

C -2.378361 -1.430787 -1.222260

H -2.783301 -1.734302 -2.197451

H -1.552399 -2.112882 -0.997834

H -3.171149 -1.586982 -0.486726

N -1.210551 1.110800 0.134187

C 0.359271 -6.092811 0.345802

C 1.482991 -5.062239 0.648150

C 1.258225 -3.965366 -0.406566

O -0.136973 -4.029775 -0.721602

C -0.457053 -5.422004 -0.780997

H 0.756647 -7.060463 0.026438

H -0.259642 -6.265497 1.230322

H 2.484161 -5.496124 0.578080

H 1.368753 -4.650701 1.654630

H 1.474212 -2.952516 -0.058679

H 1.852147 -4.161579 -1.314016

H -0.170788 -5.825287 -1.765575

H -1.539419 -5.519305 -0.666493

Si 3.242941 0.040227 0.551999

C 4.099784 -0.600964 -1.039863

H 3.973440 0.106624 -1.867857

H 5.177829 -0.740315 -0.878828

H 3.683556 -1.561530 -1.366145

C 4.205953 1.632297 1.023029

H 4.090652 2.412101 0.260691

H 3.854564 2.048602 1.974786

59

H 5.280235 1.425447 1.127242

C 3.697752 -1.227220 1.918834

H 3.333410 -0.902199 2.900613

H 3.264408 -2.214613 1.720523

H 4.787188 -1.351074 1.991521

Si -0.983324 2.944008 0.083620

C -0.403640 3.535370 -1.611558

H -1.088682 3.322364 -2.435443

H -0.308185 4.626906 -1.543421

H 0.582442 3.139281 -1.870873

C -2.623734 3.814519 0.456707

H -3.422291 3.526005 -0.232535

H -2.979666 3.642362 1.476857

H -2.469702 4.895559 0.348600

C 0.298240 3.607132 1.301014

H 0.092196 3.380558 2.347769

H 1.306008 3.250805 1.068663

H 0.299580 4.701306 1.195299

Si 2.957205 3.058568 -5.411484

C 4.602118 3.821560 -4.860265

H 5.291310 3.910348 -5.712285

H 4.458138 4.823003 -4.441442

H 5.090497 3.206012 -4.097889

C 2.103278 4.170705 -6.689534

H 2.721881 4.267079 -7.593301

H 1.133835 3.759953 -6.990672

H 1.933042 5.177058 -6.292858

C 3.232982 1.323896 -6.123672

H 3.893603 1.367973 -7.001453

H 3.698125 0.660199 -5.387674

H 2.289131 0.866791 -6.438532

--------------------------------------------------------

60

Supplementary Table S31 | Cartesian coordinate of TS between IX-SiMe3 and X in the quintet state. Units are presented in Å.




--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe 0.938867 0.777206 -0.356659

Si -1.602676 0.581841 1.412526

C -0.982412 1.659590 2.834184

H 0.106654 1.759943 2.833897

H -1.427725 2.656634 2.883816

H -1.260904 1.135651 3.758067

C -0.865675 -1.124989 1.722027

H 0.197652 -1.048147 1.968417

H -1.378052 -1.548601 2.597725

H -0.964378 -1.838922 0.903340

C -3.486130 0.486749 1.605226

H -3.707455 0.127482 2.618205

H -3.963000 1.464938 1.493932

H -3.967632 -0.203341 0.907046

Si -1.979892 0.430605 -1.664903

C -0.889834 0.465802 -3.202056

H -0.643889 1.467048 -3.558367

H 0.052184 -0.067952 -3.035942

H -1.428241 -0.056716 -4.004396

C -3.652789 1.224392 -2.062296

H -3.591901 2.268440 -2.380447

H -4.105308 0.660243 -2.887566

H -4.342382 1.168374 -1.214040

C -2.326639 -1.392286 -1.340628

H -2.857638 -1.751506 -2.232924

H -1.424583 -2.002565 -1.239342

H -2.975181 -1.592151 -0.484244

N -1.168593 1.283493 -0.241969

C 0.655730 -6.000334 0.175151

C 1.887531 -5.067641 0.005440

C 1.386837 -3.983676 -0.965120

O -0.032245 -3.939645 -0.781615

C -0.448043 -5.301167 -0.647709

H 0.845466 -7.012747 -0.192603

H 0.369644 -6.079170 1.227339

H 2.762897 -5.591750 -0.387804

H 2.169742 -4.621612 0.962828

H 1.778761 -2.984317 -0.765189

H 1.617046 -4.251763 -2.009161

H -0.542900 -5.758947 -1.645522

H -1.430236 -5.303452 -0.168946

Si 3.239060 0.171962 0.274316

C 4.294907 -0.632191 -1.108710

H 4.413461 0.046565 -1.960479

H 5.298347 -0.885289 -0.739596

H 3.836434 -1.553075 -1.488058

C 4.269558 1.669313 0.886786

H 4.376216 2.436023 0.110850

61

H 3.801800 2.147135 1.755941

H 5.278567 1.352105 1.184948

C 3.304424 -1.075401 1.733999

H 2.835104 -0.662504 2.635239

H 2.789603 -2.014268 1.498292

H 4.345273 -1.320767 1.987053

Si -1.169452 3.127039 -0.332888

C -0.956271 3.735831 -2.106440

H -1.744908 3.434035 -2.799595

H -0.966458 4.832682 -2.061358

H 0.009694 3.437201 -2.527422

C -2.795906 3.836455 0.325554

H -3.673678 3.446332 -0.197346

H -2.936223 3.666357 1.397092

H -2.777426 4.922890 0.172230

C 0.239977 3.937772 0.626140

H 0.233416 3.738112 1.698444

H 1.220272 3.649132 0.235037

H 0.134126 5.023457 0.491876

Si 2.773124 2.494248 -4.129325

C 4.418496 3.195420 -3.497119

H 5.110624 3.367822 -4.333964

H 4.273361 4.150252 -2.980820

H 4.902613 2.506954 -2.797317

C 1.955903 3.746561 -5.304875

H 2.614377 3.954852 -6.160647

H 1.007809 3.366464 -5.700154

H 1.752608 4.698068 -4.802167

C 3.066236 0.862498 -5.052444

H 3.752484 1.016694 -5.897685

H 3.506263 0.105390 -4.395837

H 2.129748 0.458680 -5.451357

--------------------------------------------------------

62

Supplementary Table S32 | Cartesian coordinate of X in the quintet state. Units are presented in Å.



--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe 0.611897 0.822864 0.160512

Si -2.136556 -0.219299 1.801673

C -1.746719 0.869185 3.291880

H -0.697602 1.171368 3.328172

H -2.373025 1.761620 3.369657

H -1.938598 0.261117 4.184941

C -1.148047 -1.817644 1.987427

H -0.151030 -1.773157 1.541441

H -1.017588 -2.008420 3.059070

H -1.668645 -2.677335 1.560816

C -3.967859 -0.683096 1.937764

H -4.112148 -1.179501 2.906171

H -4.635621 0.182150 1.911444

H -4.293819 -1.386883 1.166786

Si -2.315128 -0.275330 -1.263543

C -1.267225 0.094992 -2.780299

H -1.216748 1.146696 -3.060152

H -0.242727 -0.269220 -2.656463

H -1.712271 -0.453716 -3.620955

C -4.128065 0.107168 -1.661232

H -4.319992 1.147937 -1.934875

H -4.420552 -0.510879 -2.519531

H -4.795292 -0.151827 -0.833520

C -2.211766 -2.144331 -1.048330

H -2.509832 -2.562442 -2.019397

H -1.206639 -2.521685 -0.839341

H -2.901277 -2.554477 -0.306361

N -1.758889 0.656271 0.227953

C 2.792966 -5.253813 -0.615256

C 2.956364 -4.395133 -1.899890

C 1.506419 -4.097901 -2.317160

O 0.747919 -4.143066 -1.106256

C 1.268500 -5.250613 -0.364483

H 3.171310 -6.271853 -0.744732

H 3.329625 -4.801772 0.222227

H 3.510304 -4.913449 -2.687656

H 3.484460 -3.465336 -1.673710

H 1.363626 -3.111338 -2.764175

H 1.132906 -4.861404 -3.019724

H 0.808536 -6.184633 -0.725373

H 0.990030 -5.107963 0.682312

Si 2.287188 0.026793 1.899813

C 3.060983 -1.640625 1.356314

H 3.530619 -1.557530 0.369768

H 3.833783 -1.956484 2.070642

H 2.311477 -2.437790 1.295869

C 3.752226 1.252454 2.033925

H 4.256670 1.413528 1.076302

H 3.425010 2.231382 2.403105

63

H 4.497962 0.863912 2.741105

C 1.774721 -0.237081 3.730556

H 1.425832 0.691751 4.196519

H 0.988498 -0.988653 3.851489

H 2.649512 -0.578584 4.301119

Si 2.025902 1.990299 -1.605184

C 1.382931 2.503841 -3.339524

H 0.564820 3.231746 -3.296903

H 2.206641 2.976650 -3.892170

H 1.039525 1.648149 -3.929808

C 2.734228 3.619248 -0.884284

H 1.949288 4.375347 -0.759829

H 3.209210 3.472936 0.090860

H 3.488510 4.039225 -1.563931

C 3.531200 0.874561 -2.010779

H 4.080478 0.565535 -1.115901

H 3.216585 -0.035635 -2.535404

H 4.232781 1.408575 -2.666123

Si -2.198518 2.443284 0.220137

C -3.932540 2.754773 0.909206

H -4.032534 2.509464 1.970259

H -4.146115 3.826174 0.805949

H -4.708395 2.212767 0.360650

C -2.153047 3.180553 -1.515519

H -2.863758 2.747319 -2.222387

H -2.409075 4.242521 -1.408561

H -1.154964 3.131919 -1.956938

C -0.977970 3.479088 1.221737

H 0.042599 3.425064 0.826831

H -1.299968 4.525617 1.135106

H -0.941805 3.233566 2.284084

--------------------------------------------------------

64

Supplementary Table S33 | Cartesian coordinate of TS between X and I-N(SiMe3)3 in the quintet state. Units are presented in Å.




--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe 1.184505 0.617485 -0.944983

Si -1.200320 0.761864 1.485349

C -0.193956 1.931131 2.573015

H 0.867353 1.945551 2.315038

H -0.563793 2.959454 2.580602

H -0.275630 1.551777 3.599585

C -0.548385 -0.982833 1.785967

H 0.342070 -1.208850 1.193455

H -0.260531 -1.058202 2.841078

H -1.296635 -1.752774 1.589249

C -2.974021 0.831121 2.147319

H -2.946336 0.555278 3.209385

H -3.411586 1.831270 2.080354

H -3.652387 0.130772 1.652236

Si -2.282419 0.310052 -1.352008

C -1.667910 0.147749 -3.122511

H -1.537348 1.094006 -3.646991

H -0.719341 -0.394389 -3.168751

H -2.412480 -0.440143 -3.675119

C -3.990091 1.130438 -1.377476

H -4.000144 2.125653 -1.829930

H -4.657576 0.497963 -1.976565

H -4.428918 1.210953 -0.378405

C -2.551127 -1.463631 -0.769053

H -3.204342 -1.928397 -1.519427

H -1.617792 -2.033530 -0.744354

H -3.056843 -1.557299 0.194899

N -1.104800 1.230646 -0.285653

C 1.346219 -4.435712 -2.891328

C 1.522829 -4.831821 -1.417216

C 1.480668 -3.470102 -0.721969

O 0.589332 -2.648284 -1.508196

C 0.359136 -3.269335 -2.791995

H 2.298973 -4.094651 -3.310827

H 0.969236 -5.248895 -3.517699

H 2.453497 -5.371947 -1.222856

H 0.687619 -5.459431 -1.085433

H 1.093342 -3.511787 0.300474

H 2.472842 -3.001176 -0.701072

H 0.502239 -2.517034 -3.573531

H -0.682181 -3.618914 -2.831259

Si 3.118322 0.448661 0.703762

C 4.582586 -0.470853 -0.124832

H 4.920062 0.021688 -1.041918

H 5.435784 -0.506660 0.566408

H 4.321935 -1.503949 -0.382616

C 3.834602 2.165124 1.174884

H 4.061482 2.771652 0.290952

65

H 3.146678 2.744734 1.801354

H 4.768117 2.042295 1.741048

C 2.926480 -0.462994 2.383215

H 2.186591 0.004631 3.040848

H 2.635431 -1.511041 2.250020

H 3.890389 -0.452333 2.910341

Si -1.058997 3.040303 -0.599293

C -1.331556 3.472962 -2.416179

H -2.301264 3.177265 -2.822916

H -1.278172 4.567747 -2.476562

H -0.547795 3.075256 -3.064614

C -2.412116 3.949812 0.366556

H -3.415220 3.588486 0.121145

H -2.290771 3.899028 1.452270

H -2.369042 5.010393 0.087979

C 0.596061 3.826876 -0.152511

H 0.852509 3.774806 0.906126

H 1.429305 3.406042 -0.724192

H 0.525931 4.889526 -0.421175

Si 2.288773 0.977528 -3.201663

C 3.620396 2.342720 -2.988059

H 4.187156 2.465782 -3.921273

H 3.171044 3.313725 -2.746968

H 4.337632 2.107145 -2.194967

C 1.329242 1.524597 -4.771574

H 2.036308 1.613617 -5.607941

H 0.558089 0.805490 -5.066441

H 0.847572 2.501193 -4.651369

C 3.241732 -0.580365 -3.788599

H 3.880433 -0.329693 -4.646803

H 3.883031 -0.998658 -3.006559

H 2.554540 -1.370717 -4.113368

--------------------------------------------------------

66

Supplementary Table S34 | Cartesian coordinate of I-N(SiMe3)3 in the quintet state. Units are presented in Å.



--------------------------------------------------------


X Y Z

--------------------------------------------------------

Fe 6.791402 2.424005 0.087002

Si -0.632051 2.638885 1.333870

C -0.292503 3.251569 3.092719

H 0.730155 3.620159 3.214950

H -0.979838 4.020535 3.454375

H -0.405619 2.383080 3.754284

C 0.788008 1.426582 0.996825

H 1.717936 1.971320 0.795936

H 0.947375 0.816733 1.895110

H 0.601373 0.745643 0.163580

C -2.272791 1.697066 1.418278

H -2.199252 0.858698 2.122117

H -3.072912 2.356951 1.773569

H -2.589013 1.290135 0.453131

Si -0.983658 3.550146 -1.589171

C 0.241175 4.419360 -2.738845

H 0.036133 5.481066 -2.888245

H 1.266368 4.323746 -2.363002

H 0.205883 3.937390 -3.723931

C -2.762296 3.956557 -2.094203

H -3.031356 5.002708 -1.920241

H -2.915610 3.750627 -3.160755

H -3.471039 3.337525 -1.531768

C -0.743193 1.709407 -1.977116

H -1.074653 1.562235 -3.012994

H 0.308961 1.412087 -1.932032

H -1.322329 1.022927 -1.354220

N -0.710193 3.944698 0.127354

C 4.290255 -1.170199 0.690684

C 4.436316 -1.198377 -0.839600

C 4.840844 0.237361 -1.158541

O 5.608537 0.681791 0.008216

C 5.440369 -0.262466 1.116560

H 3.328918 -0.729144 0.974495

H 4.361335 -2.160867 1.147016

H 3.515465 -1.486843 -1.352764

H 5.226798 -1.895182 -1.138804

H 5.479732 0.342038 -2.037116

H 3.974445 0.899267 -1.259729

H 5.246296 0.316550 2.020970

H 6.381289 -0.810528 1.233499

Si 8.043281 2.899582 2.209268

C 9.869907 2.334065 2.128133

H 10.396181 2.802561 1.288651

H 10.403960 2.603949 3.049597

H 9.951997 1.248073 2.001544

C 8.083401 4.776051 2.573628

H 8.556843 5.332613 1.756682

H 7.073809 5.182018 2.705487

67

H 8.650794 4.983906 3.491107

C 7.316803 2.078960 3.785268

H 6.281531 2.393119 3.964342

H 7.327320 0.984335 3.715432

H 7.903609 2.356247 4.671918

Si 6.865391 3.912521 -1.931435

C 6.361296 3.080966 -3.586218

H 5.321323 2.733073 -3.568517

H 6.454667 3.791428 -4.419230

H 6.998931 2.218892 -3.816475

C 5.727853 5.442600 -1.755402

H 4.673045 5.156550 -1.667972

H 5.983099 6.030808 -0.866522

H 5.823453 6.100877 -2.629892

C 8.628221 4.597104 -2.215370

H 8.980391 5.170858 -1.350498

H 9.350655 3.791823 -2.391590

H 8.650442 5.263953 -3.088163

Si -0.832261 5.640722 0.672882

C -2.443028 5.913305 1.631144

H -2.553829 5.252085 2.495910

H -2.499321 6.945719 1.997779

H -3.307939 5.746672 0.978263

C -0.865567 6.883946 -0.754609

H -1.626275 6.694679 -1.516088

H -1.091617 7.861655 -0.310164

H 0.105408 6.972919 -1.250214

C 0.652634 6.170365 1.717318

H 1.592194 5.859821 1.246291

H 0.666135 7.265425 1.782398

H 0.641461 5.783619 2.738127

--------------------------------------------------------

68

Supplementary Methods

1. Experimental Details

General Method. GLC analyses were carried out on a Shimadzu GC-2014 instrument

equipped with a flame-ionization detector using a CBP10 fused silica capillary column (25 m

x 0.25 mm). GC-MS spectra were recorded on a Shimadzu GC-2010/PARVUM2 instrument.

Solvents were dried over appropriate reagents and distilled prior to use. Sodium (30wt%

dispersion in toluene, Across Organics) and lithium (30wt% dispersion in paraffin, Kanto

Chemical) metals were washed with hexane and then with THF, and were stored in an argon-

filled glovebox. Chlorotrimethylsilane were distilled before use. Ferrocene was sublimated

before use. Complexes [Fe(CO)4(SiMe3)2],16 [Fe3(CO)12],46 [{η5-C5H4(SiMe3)}2Fe],47 and

[{η5-C5H2(SiMe3)3}2Fe ]17 were prepared as described in the literatures.

Catalytic Reduction of N2 into N(SiMe3)3 in the Presence of Fe(CO)5. A typical

procedure (Supplementary Table S1, run 1) is as follows. To a suspension of sodium (1.38

g, 60 mmol) in THF (40 mL) were added Me3SiCl (7.6 mL, 60 mmol) and Fe(CO)5 (13.2 µL,

0.10 mmol) under dinitrogen atmosphere. The mixture was stirred at room temperature (22-

24 °C) for 20 h under a gentle stream of dinitrogen. To the reaction mixture was added

cyclododecane (0.100 g) as an internal standard for GLC analysis. After stirring for 5 min,

the mixture was centrifuged to remove insoluble materials. The resultant clear supernatant

was subjected to GLC and GC-MS analyses. Then the supernatant was stirred with an

aqueous solution of H2SO4 (0.5 M, 10 mL) for 12 h. After the addition of an aqueous

solution of KOH (30 wt %, 10 mL), ammonia was distilled into an aqueous solution of

H2SO4 (0.5 M, 10 mL) under reduced pressure. The amount of ammonia was determined by

the indophenol method.48

69

Separately, we confirmed that the following Fe-complexes such as [(η5-C5H4R)2Fe] (R =

Me, tBu), FeCl2, and [Fe{N(SiMe3)2}2] did not work as effective catalysts under the same

reaction conditions (Supplementary Table S2).

Time Profile of Catalytic Formation of N(SiMe3)3 from N2. To a suspension of

sodium (1.38 g, 60 mmol) in THF (40 mL) were added Me3SiCl (7.6 mL, 60 mmol), Fe(CO)5

(13.2 µL, 0.10 mmol), and cyclododecane (0.102 g) under dinitrogen atmosphere. The

mixture was stirred at room temperature under a gentle stream of dinitrogen. An aliquot of

the reaction mixture was periodically analyzed by GLC (Supplementary Table S3).

2. Computational details

1. Fe(SiMe3)2X (X = thf (I), Cl– (I')), and their N2 complexes (II and II'). Optimized

structures of the proposed catalytic complexes I and I' as well as their N2 complexes (II and

II') are presented in Supplementary Figure S1. Both I and I' have a triangular structure and

their electronic ground state is triplet. The quintet and singlet states are higher in energy than

the triplet state by 4.1 and 33.0 kcal/mol for I, and 5.4 and 37.5 kcal/mol for I', respectively.

The Fe–N2 complexes II and II' adopt a slightly deformed tetrahedral structure. The N≡N

bond distance (rNN) and the N≡N stretching frequency (νNN) are calculated to be 1.126 Å and

2122 cm–1 for II, and 1.131 Å and 2082 cm–1 for II'. These values suggest that the

coordinated N2 molecule is activated in both the systems (cf. rNN = 1.098 Å and νNN = 2422

cm–1 for free N2 molecule). For the Fe–N2 complexes, the electronic ground state is quintet,

and the triplet state lies 4.3 (II) and 1.9 (II') kcal/mol above the quintet state. The N2-

binding energy in the Fe–thf system is 3.7 kcal/mol (quintet) and 12.1 kcal/mol (triplet),

while the N2 binding energy in the Fe–Cl system is only 0.3 kcal/mol (quintet) and 7.7

70

kcal/mol (triplet). Based on the strength of the Fe–N2 bond, the triplet state of

Fe(SiMe3)2(thf) (I) should be a better candidate for the catalyst of the N2 conversion.

2. Optimized structures of intermediates and energy profile for each reaction step in the

catalytic transformation of N2 into N(SiMe3)3 by I. Supplementary Figure S2 shows the

calculated catalytic cycle and energy profile of the transformation of N2 into N(SiMe3)3

catalyzed by I. Supplementary Figures S3-S10 describes energy profiles for each reaction

step presented in Supplementary Figure S2, together with optimized structures of reactant

complexes, transition states (TS), and product complexes. Selected interatomic distances of

the optimized structures are given in Å and hydrogen atoms are omitted for clarity in the

Supplementary Figures.

As shown in Supplementary Figure S2, the proposed reaction pathway for the conversion of

N2 into N(SiMe3)3 involves 10 iron complexes I-X, where a Me3Si radical is assumed to

work as an active species generated in situ from Na and Me3SiCl. The catalytic cycle starts

with the N2 binding to I. The difference in the SCF energy between I–N2 and TS is

estimated to be only 0.01 kcal/mol in the triplet state and it reverses by considering the zero-

point energy correction. Thus, we regard that the N2 addition has no activation barrier. A

sequential addition of two trimehylsilyl radicals to the distal N atom of the coordinated N2 in

II proceeds to form IV via III (Supplementary Figures S3 and S4). The addition of a silyl

radical to the distal N atom of IV results in the formation of V, in which the activation energy

is calculated to be relatively high (12.0 kcal/mol) due to steric hindrance among bulky silyl

ligands (Supplementary Figure S5). The N–N bond in V is readily cleaved to generate the

71

first molecule of N(SiMe3)3 and VI derived from a nitrido (Fe≡N) intermediate

(Supplementary Figure S6). The nitrido intermediate [Fe(SiMe3)2(thf)(N)] cannot be

optimized and the two silyl ligands on the Fe atom are spontaneously migrated to the N atom,

resulting in the formation of [Fe(N(SiMe3)2)(thf)] VI. The next silyl radical attacks the Fe

atom of VI to form VII. We could not optimize a reactant complex VI–SiMe3 even though

the geometry optimization started from the Fe–Si distance of 7 Å. This reaction virtually has

no activation barrier and thus the energy change were calculated using a thermochemical

equation VI + Me3Si = VII. After the addition of SiMe3 radical to VII (Supplementary

Figure S7), one of the silyl groups on the Fe atom migrates to the N atom to form IX having

the N(SiMe3)3 group as a ligand (Supplementary Figure S8). This migration process

temporally liberates the coordinated THF molecule. The formation of X from IX and SiMe3

is followed by the release of the second molecule of N(SiMe3)3 and the regeneration of I.

(Supplementary Figures S9 and S10). The highest activation energy in all the reaction steps

is 19.0 kcal/mol calculated for VIII → IX, which is reasonably low for a reaction that

proceeds at root temperature. In conclusion, the computational results suggest that the Fe(II)

complex I bearing two Me3Si groups is capable of serving as a suitable catalyst for the

transformation of N2 into N(SiMe3)3

72

Supplementary References

46. W. McFarlane, G. Wilkinson, Inorg. Synth. 8, 181 (1966).

47. A. F. Cunningham Jr. J. Am. Chem. Soc. 113, 4864 (1991).

48. A. L. Chaney, E. P. Marbach, Clinical Chem. 8, 130 (1962).

i ii - nature...v 0.0 quartet 1.498 1.777 ts (461 i) 4.1 kcal/mol –121.9 kcal/mol quartet quartet...

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