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Supporting Information

Facile Synthesis of a Nickel(0) Phosphine Complex at Ambient Temperature

Schirin Hanf,a Toni Grell,b Raúl García-Rodríguez,c Evamarie Hey-Hawkins*,b and Dominic S. Wright*,a

a Dr. S. Hanf, Prof. Dr. D. S. Wright, Chemistry Department, Cambridge University, Lensfield Road, CB2 1EW, Cambridge, UK. E-mail: dsw1000@cam.ac.uk

b Dr. T. Grell, Prof. Dr. E. Hey-Hawkins, Institute of Inorganic Chemistry, Faculty of Chemistry and Mineralogy, Leipzig University, Johannisallee 29, 04103 Leipzig, Germany. E-mail: hey@uni-leipzig.de

c Dr. R. García-Rodríguez, GIR MIOMeT-IU Cinquima-Química Inorgánica Facultad de Ciencias, Universidad de Valladolid, Campus Miguel, Delibes, 47011 Valladolid, Spain.

Electronic Supplementary Material (ESI) for ChemComm.This journal is © The Royal Society of Chemistry 2020

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1. Experimental Details

All experiments were carried out on a Schlenk-line under a dry, oxygen-free nitrogen atmosphere or

with the aid of an N2-filled glove box (MBraun lab star 50). All solvents were freshly distilled over

appropriate drying agents under nitrogen or taken from a solvent purification system (SPS-800,

MBraun). Solvents were subsequently stored over molecular sieves. Deuterated solvents were dried

over P2O5 or CaH2. Ligand 11 and [Ni(MeCN)6](BF4)22 were synthesised according to literature

procedures.

Synthesis of 2

(MeO)2P(2-py) (1) (0.16 g, 0.95 mmol) in 3 mL acetonitrile was added to [Ni(MeCN)6](BF4)2 (76 mg, 0.16

mmol) in 3 mL acetonitrile. The mixture turned brown/red immediately and was stirred overnight.

Then the solvent was removed in vacuo, and the nickel complex 2·MeOH was crystallised from a

saturated methanol solution at –20 °C. Crystalline yield: 55 mg, 0.058 mmol, 37 % (based on

[Ni(MeCN)6](BF4)2). 1H NMR (CD3CN, 400.16 MHz), δ [ppm] = 8.88 (1H, d, JHH = 5.3 Hz, H6), 8.31 (1H, t,

JHH = 7.8 Hz, H4), 8.03 (1H, t, JHH = 7.9 Hz, H3), 7.83–7.77 (1H, m, H5), 3.06 (6H, s, br, CH3), N–H cannot

be unambiguously assigned. 31P{1H} NMR (CD3CN, 161.99 MHz), δ [ppm] = 154.5 (s). 11B{1H} NMR

(CD3CN, 128.38 MHz), δ [ppm] = –1.2 (s). 19F{1H} NMR (CD3CN, 376.50 MHz), δ [ppm] = –151.9 (s). 13C{1H} NMR (CD3CN, 100.63 MHz), δ [ppm] = 159.5 (s, C2), 145.2 (s, C6), 142.3 (s, C4), 127.2 (s, C3),

125.9 (s, C5), 52.0 (s, CH3). ATR-IR, ν [cm-1] = 3427 (br, m), 2946 (w), 2839 (w), 2039 (br, w), 1641 (w),

1602 (m), 1493 (w), 1472 (w), 1443 (m), 1058 (s), 1034 (s), 1001 (s), 764 (s). Elemental analysis, calcd.

[%] for [{(MeO)2P(2-py-H)}2{(MeO)2P(2-py)}2Ni](BF4)2, C 36.7, H 4.6, N 6.1; found C 36.1, H 4.2, N 6.2.

HR-MS (ESI, –) m/z: 1005.1412, calcd. 1005.1400 (1.2 ppm error), [M+BF4]–.

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2. Nuclear Magnetic Resonance Spectroscopy

NMR spectra were recorded on a Bruker Avance DRX 400 spectrometer or a Bruker Avance III HD 400

(298 K). All spectra were recorded in dry CDCl3 or CD3CN with SiMe4 as an internal standard. 1H and 13C

NMR spectra were referenced to TMS, whereas all other heteronuclei were referenced to TMS via the

Ξ scale.3 Unambiguous assignments of the NMR resonances were made on the basis of 2D NMR

experiments (1H-1H COSY, 1H-13C HSQC, 1H-13C HMBC experiments). Scheme S1 shows the labelling

scheme for the NMR assignments used in the experimental section.

P2

OMe4

5 6N

OMe

H6

H5

H4H3

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Scheme S1. Atom labelling scheme used in the NMR studies for the 2-pyridyl-phosphine ligand.

Figure S1. 1H NMR (400.13 MHz, CDCl3) spectrum of (MeO)2P(2-py) (1).

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Figure S2. 31P{1H} NMR (161.98 MHz, CDCl3) spectrum of (MeO)2P(2-py) (1).

Figure S3. 31C{1H} NMR (100.63 MHz, CDCl3) spectrum of (MeO)2P(2-py) (1).

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Figure S4. 1H NMR (400.13 MHz, CD3CN) spectrum of [{(MeO)2P(2-py-H)}2{(MeO)2P(2-py)}2Ni](BF4)2·MeOH (2·MeOH).

Figure S5. 31P{1H} NMR (161.99 MHz, CD3CN) spectrum of [{(MeO)2P(2-py-H)}2{(MeO)2P(2-py)}2Ni](BF4)2·MeOH (2·MeOH).

Figure S6. 11B{1H} NMR (128.38 MHz, CD3CN) spectrum of [{(MeO)2P(2-py-H)}2{(MeO)2P(2-py)}2Ni](BF4)2·MeOH (2·MeOH).

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Figure S7. 19F{1H} NMR (376.50 MHz, CD3CN) spectrum of [{(MeO)2P(2-py-H)}2{(MeO)2P(2-py)}2Ni](BF4)2·MeOH (2·MeOH).

Figure S8. 13C{1H} NMR (100.63 MHz, CD3CN) spectrum of [{(MeO)2P(2-py-H)}2{(MeO)2P(2-py)}2Ni](BF4)2·MeOH (2·MeOH).

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3. IR Spectroscopy

IR measurements of the KBr pellets were conducted with a Perkin Elmer FT IR Spectrum 2000.

Figure S9. IR spectrum of 2·MeOH, measured as a KBr pellet in the solid state.

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4. Mass spectrometry

High-resolution ESI MS measurements were carried out in positive or negative ion mode under

electrospray ionisation on a Bruker Impact II apparatus.

Figure S10. HR MS spectrum of the isolated crystals of 2.

Figure S11. Section of the HR MS spectrum: main peak of the isolated crystals of 2.

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Figure S12. Simulated isotopic pattern of the main peak of 2.

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5. Single-crystal X-ray crystallography

Single crystal diffraction data were collected with a GEMINI CCD diffractometer (RIGAKU) with Mo-Kα

radiation (λ = 0.71073 Å). The absorption corrections were carried out semiempirically with the SCALE3

ABSPACK module.4 All data were corrected for Lorentz polarisation and long-term intensity

fluctuations. The structure of 2 was solved with SHELXT-2014 (dual-space method).5 Anisotropic

refinement of all non-hydrogen atoms was done with SHELXL-20176 by using full-matrix least-square

routines against F2. Unless otherwise stated all hydrogen atoms were calculated on idealised positions.

For the structure of 2 the hydrogen atoms H31 and H32 (attached to N1 and N3) were detected as

significant residual electron density maxima and were refined with only restrained distance:

x y z sof U Peak Distances to nearest atoms (including eq.)

Q4 1 1.0825 -0.0008 0.2482 1.00000 0.05 0.92 0.84 N3

Q9 1 0.7447 0.5293 0.2555 1.00000 0.05 0.65 0.93 N1

Exchanging the scattering factors of the ortho-atoms within the pyridyl rings (nitrogen and carbon)

leads to significant drop of the R-values and generates several errors within CheckCif.

The picture was generated with the program Diamond.7 CCD 1956107 (2) contains the supplementary

crystallographic data for this paper. These data can be obtained free of charge via

https://summary.ccdc.cam.ac.uk/structure-summary-form (or from the Cambridge Crystallographic

Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: (+44)1223-336-033; or

deposit@ccdc.cam.uk).

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Table S1. Crystallographic data of 2.

CCDC Number 1956107Empirical formula C29H46B2F8N4NiO9P4MW (g·mol–1) 950.91Temperature (K) 130(2)Wavelength (Å) 0.71073 Crystal system TriclinicSpace group P1a ( Å)b (Å)c (Å)α (°)β (°)γ (°)

8.9718(3)14.0281(4)17.3940(6)81.344(3)82.327(3)74.196(3)

Volume (Å3) 2072.54(12)Z 2ρ (calc. in Mg·m–3) 1.524μ (mm–3) 0.711F(000) 980Crystal size (mm3) 0.20 x 0.10 x 0.10θ range for data collection (°) 2.039 – 34.937Index ranges –12 ≤ h ≤ 14,

–22 ≤ k ≤ 22, –27 ≤ l ≤ 27

Reflections collected 41003Independent reflections 16682 [R(int) = 0.0282]Completeness (%) to 25.242° 100.0Max. and min. transmission 1.00000 and 0.97959Data / restraints / parameters 16682 / 3 / 572GooF on F2 1.019Final R indices [I>2σ(I)]

R1 = 0.0505, wR2 = 0.1248

R indices (all data) R1 = 0.0725, wR2 = 0.1384

Largest diff. peak and hole e·Å–3 1.863 and –0.923

References

1 S. Hanf, R. García-Rodríguez, S. Feldmann, A. D. Bond, E. Hey-Hawkins, D. S. Wright, Dalton Trans., 2017, 46, 814.

2 A. Sen, T. W. Lai, R. R. Thomas, J. Organomet. Chem., 1988, 358, 567.3 R. K. Harris, E. D. Becker, S. M. Cabral De Menezes, R. Goodfellow, P. Granger, Concepts

Magn. Res., 2002, 14, 326. 4 Empirical absorption correction. CrysAlis-Pro Software package; Oxford Diffraction Ltd., 2014.5 G. M. Sheldrick, Acta Cryst A, 2015, 71, 3.6 G. M. Sheldrick, Acta Cryst C, 2015, 71, 3.7 Diamond - Crystal and Molecular Structure Visualization, Crystal Impact, H. Putz, K.

Brandenburg GbR, Kreuzherrenstr. 102, 53227 Bonn, Germany.