nickel and cobalt catalyzed asymmetric codimerisation of alkenes guillaume pelletier litterature...
Post on 13-Dec-2015
248 Views
Preview:
TRANSCRIPT
Nickel and Cobalt catalyzed asymmetric codimerisation of alkenes
Guillaume Pelletier
Litterature meeting October 26th 2010
R1H
Ni, Rh, Pd, Co, Ru
cat. H*
Challenges in asymmetric catalysis
• Activation of stable molecules:Use of abundantly available, preferably neutral, starting materials and prochiral substrates
(Alkynes, alkenes, carbonyl compounds, CO, CO2, HCN, H2, N2)
• Efficiency and selectivity: High turnover frequencies (substrate/catalyst/time) High reagent-based chemo- regio- and stereoselectivities
• Large-scale synthesis: Ambient reaction conditions Post-reaction recovery of products Cost of metal/ligands
An example of a very efficient industrial catalytic process : Ziegler-Natta polymerisation
TiCl Cl
Cl Cl
L
M = Al, Li, Mg, Zn...L is an unspecified ligand
+ M-R' TiCl Cl
Cl
L
R'
"Active-Catalyst"
- M-Cl +R
TiCl Cl
Cl
L
R'
R
Carbo-metallation
TiCl Cl
Cl
L
+R
TiCl Cl
Cl
L
R'
R
R'
R
R
Carbo-metallation
TiCl Cl
Cl
L
R
R'
RRepeat "n"
times
TiCl Cl
Cl
L
R
R'
R
n-H or
reductive termination
Polymers(HDPE + others)
Britovsek, G. J. P.; Gibson, V. C.; Wass, D. F., Angew. Chem., Int. Ed. 1999, 38, 428-447.Corradini, P.; Guerra, G.; Cavallo, L., Acc. Chem. Res. 2004, 37, 231-241.
• “In 2010, the total volume of plastics, elastomers, and rubbers produced from alkenes with these catalysts worldwide exceeds 100 million metric tons. Together, these polymers represent the largest-volume commodity plastics as well as the largest-volume commodity chemicals in the world.”
Industrial ton-scaled cationic Nickel catalyzed process : SHOP (Shell)
Keim, W. Angew. Chem., Int. Ed. 1990, 27, 235. Wilke, W.; Bogdanović, B.; Hardt, P.; Heimbach, P.; Keim, W.; M. Kröner, M.; Oberkirch, W.; Tanaka, K.; Steinrücke, E.; Walter, D.; Zimmermann, H. Angew. Chem., Int. Ed.1966, 5, 151.
"Ni-H"
NiH
Hydrometallation
Ni
H
Ni
H
("Repeat manytimes")
n
Insertion
-olefins
-H elimination
Contemporary C-C bond formation using (asymmetric) catalysis with olefins
Metathesis (Grubbs/Shrock/Chauvin)
R1 R2Ni, W, Re, Ru, Mo
cat.
R1R2
(RCM, CM, ROM, ROMP, ADMET, Enyne)
Transfer Hydrogenation (Krische)
Reductive coupling (Montgomery/ Jamison)
Hydroformylation/Hydrocyanation/Hydrogenation/Cyclopropanation
Hydrovinylation (Wilke, Rajanbabu, Leitner)
R1 R2
H
O
R3
Ni(cod)2
Bu3P, BEt3
Toluene or THFR1
R2
R3
OH
PPh2
R1H
Ni, Rh, Pd, Co, Ru
cat.R1
H
*
*
(+)-NMDPP
R1 O
R2H
OH
R2
or
RuHCl(CO)(PPh3)3(p-anisyl)3P, m-NO2BzOH
Acetone, THF, 95 °C
R1
Me
OH
R2(Also with Ir, Rh + H2)* *
Contemporary C-C bond formation using (asymmetric) catalysis with olefins
Metathesis (Grubbs/Shrock/Chauvin)
R1 R2Ni, W, Re, Ru, Mo
cat.
R1R2
(RCM, CM, ROM, ROMP, ADMET, Enyne)
Transfer Hydrogenation (Krische)
Reductive coupling (Montgomery/ Jamison)
Hydroformylation/Hydrocyanation/Hydrogenation/Cyclopropanation
Hydrovinylation (Wilke, Rajanbabu, Leitner)
R1 R2
H
O
R3
Ni(cod)2Bu3P, BEt3
Toluene or THFR1
R2
R3
OH
PPh2
R1H
Ni, Rh, Pd, Co, Ru
cat.R1
H
*
*
(+)-NMDPP
R1 O
R2H
OH
R2
or
RuHCl(CO)(PPh3)3(p-anisyl)3P, m-NO2BzOH
Acetone, THF, 95 °C
R1
Me
OH
R2(Also with Ir, Rh + H2)* *
Challenges in catalytic hydrovinylation
R1H
Ni, Rh, Pd, Co, Ru
cat. H*
• Activation of stable olefins
• Regiochemical outcome (branched vs linear)
• Chemoselectivity outcome (Lewis basic groups, other olefins)
• Control of oligomerisation and isomerisation
• Enantioselectivity in the branched product
Importance of heterodimerisation reactions
Wilke, G. Angew. Chem., Int. Ed. 1988, 27, 185. RajanBabu, T. V. Chem. Rev. 2003, 103, 2845.RajanBabu, T. V. Synlett 2009, 853.
R1
X
Hydrovinylation
R1
X
*
*
*H
H
Me
Me Me
Me OH
OH
Pseudopterosin A-F
Me
Me O
OH
Me
MeOO
OH
Me
Ibuprofene(Advil , Motrin )
Naproxen(Aleve )
N
N
Me
Me
Me
H
O
O
HN
Me(+)-Phenserine
NH
Me
MeMe
N
NHOH
O
Me
Me
Me
Lyngbyatoxin A
Early studies on propylene homodimerisation(Dimersol)
• TON : 65’000 [Propylene/Ni] (0.0015 mol%)• Reaction proceeds in liquid propylene• With P(t-Bu)3 = HDPE, P(t-Bu)(i-Pr)2 = branched dimerisation,
P(n-Bu)3 = linear hexenes and methylpentenes.
• Catalysis can be stopped by adding NH3
NiBr
BrNi + PR3
EtAlCl2
-70 °CNi
PR3
Me
NiPR3
EtAlCl3
EtAlCl3
Me MeMe + isomers
C6H5Cl or DCM
Bogdanović, B.; Henc, B.; Löser, A.; Meister, B.; Pauling, H.; Wilke, G. Angew. Chem., Int. Ed. 1973, 12, 954.Bogdanović, B.; Spliethoff, B.; Wilke, G. Angew. Chem., Int. Ed. 1980, 19, 622.Wilke, G. Angew. Chem., Int. Ed. 1988, 27, 185.
Early studies on propylene homodimerisation
.Wilke, G. Angew. Chem., Int. Ed. 1988, 27, 185.
Other pioneering systemsPh
(Reactive olefin)
Metal catalyst
ethylene (x atm), Temp.
Ph Ph
C6 olefins
ConditionsSelectivity for
major product (%)Yield (%) Comments
PPh3
Ph3PNi
Br
Ar (6 mol%)
BF3OEt2, >1 atm C2H4 0 °C, DCM
PBn3
Bn3PNi
NCMe
Ar(0.2 mol%)
BF4
25 °C, 1-2 h, 15 atm C2H4
[Ni(MeCN)6]2+ 2BF4- (1 to 0.5 mol%)
10 atm C2H4, Et2AlCl 20 mol%,
PPh3 or dppe 4 mol%, DCM, 25 °C
PdP
O OEt
PhPh
(0.1 mol%)
BF4
15 °C, 1h, DCM, 15 atm C2H5
91 67
94 94
87 98
41 91
Moderate selectivityand yields
Styrene dimerisation
Exothermic ethylenepolymerisation
Tolerant to Cl and MeOgroups
Tolerance to Lewis basicgroups variable on Ni/Al
and order of addition
Selectivity is 9% when100% conversion.
.Kawata, N.; Maruya, K.; Mizoroki, T.; Ozaki, A. Bull. Chem. Soc. Jpn. 1971, 44, 3217.
Other pioneering systemsPh
(Reactive olefin)
Metal catalyst
ethylene (x atm), Temp.
Ph Ph
C6 olefins
ConditionsSelectivity for
major product (%)Yield (%) Comments
PPh3
Ph3PNi
Br
Ar (6 mol%)
BF3OEt2, >1 atm C2H4 0 °C, DCM
PBn3
Bn3PNi
NCMe
Ar(0.2 mol%)
BF4
25 °C, 1-2 h, 15 atm C2H4
[Ni(MeCN)6]2+ 2BF4- (1 to 0.5 mol%)
10 atm C2H4, Et2AlCl 20 mol%,
PPh3 or dppe 4 mol%, DCM, 25 °C
PdP
O OEt
PhPh
(0.1 mol%)
BF4
15 °C, 1h, DCM, 15 atm C2H5
91 67
94 94
87 98
41 91
Moderate selectivityand yields
Styrene dimerisation
Exothermic ethylenepolymerisation
Tolerant to Cl and MeOgroups
Tolerance to Lewis basicgroups variable on Ni/Al
and order of addition
Selectivity is 9% when100% conversion.
.Muller, G.; Ordinas, J. I. J. Mol. Catal., A : Chem. 1997, 125, 97.
Other pioneering systemsPh
(Reactive olefin)
Metal catalyst
ethylene (x atm), Temp.
Ph Ph
C6 olefins
ConditionsSelectivity for
major product (%)Yield (%) Comments
PPh3
Ph3PNi
Br
Ar (6 mol%)
BF3OEt2, >1 atm C2H4 0 °C, DCM
PBn3
Bn3PNi
NCMe
Ar(0.2 mol%)
BF4
25 °C, 1-2 h, 15 atm C2H4
[Ni(MeCN)6]2+ 2BF4- (1 to 0.5 mol%)
10 atm C2H4, Et2AlCl 20 mol%,
PPh3 or dppe 4 mol%, DCM, 25 °C
PdP
O OEt
PhPh
(0.1 mol%)
BF4
15 °C, 1h, DCM, 15 atm C2H5
91 67
94 94
87 98
41 91
Moderate selectivityand yields
Styrene dimerisation
Exothermic ethylenepolymerisation
Tolerant to Cl and MeOgroups
Tolerance to Lewis basicgroups variable on Ni/Al
and order of addition
Selectivity is 9% when100% conversion.
.Fassina, V.; Ramminger, C.; Seferin, M.; Monteiro, A. L. Tetrahedron 2000, 56, 7403.
Other pioneering systemsPh
(Reactive olefin)
Metal catalyst
ethylene (x atm), Temp.
Ph Ph
C6 olefins
ConditionsSelectivity for
major product (%)Yield (%) Comments
PPh3
Ph3PNi
Br
Ar (6 mol%)
BF3OEt2, >1 atm C2H4 0 °C, DCM
PBn3
Bn3PNi
NCMe
Ar(0.2 mol%)
BF4
25 °C, 1-2 h, 15 atm C2H4
[Ni(MeCN)6]2+ 2BF4- (1 to 0.5 mol%)
10 atm C2H4, Et2AlCl 20 mol%,
PPh3 or dppe 4 mol%, DCM, 25 °C
PdP
O OEt
PhPh
(0.1 mol%)
BF4
15 °C, 1h, DCM, 15 atm C2H5
91 67
94 94
87 98
41 91
Moderate selectivityand yields
Styrene dimerisation
Exothermic ethylenepolymerisation
Tolerant to Cl and MeOgroups
Tolerance to Lewis basicgroups variable on Ni/Al
and order of addition
Selectivity is 9% when100% conversion.
.Britovsek, G. J. P.; Keim, W.; Mecking, S.; Sainz, D.; Wagner, T. J. Chem. Soc., Chem. Commun. 1993, 1632
One of the most efficient system : Wilke’s chiral azaphospholane
• Can be applied to 4-Cl-, 4-isobutyl-, 2-methylstyrene, and 2-methoxy-6-vinylnaphtalene.
• Lewis basic functionalities are not tolerated• Only the (R,R)-azaphospholane give high ee values, yields.• Modification of the ligand corresponds to drastic drop of
stereoselectivity.• Et3Al2Cl3 is highly pyroforic.
Wilke, G. Angew. Chem., Int. Ed. 1988, 27, 185. Wilke, G.; Monkiewciz, J.; Kuhn, H., US Patent, 4912274, 1990.
NiCl
ClNi
(1 atm)
(0.05 mol%)
Et3Al2Cl3 (0.15 mol%)PR3* (0.05 mol%)
-60 °C, 2.5 h, DCM 97% yield, 93% ee
NiCl
ClNi
(1 atm)
(1.2 mol%)
Et3Al2Cl3 (1.2 mol%)PR3* (1.2 mol%)
-70 °C, 2.5 h, DCM 35% yield, 92% ee
P
NMe
H Ph
MeP
NMe
HPhMe
One of the most efficient system : Wilke’s chiral azaphospholane
• Can be applied to 4-Cl-, 4-isobutyl-, 2-methylstyrene, and 2-methoxy-6-vinylnaphtalene.
• Lewis basic functionalities are not tolerated• Only the (R,R)-azaphospholane give high ee values, yields.• Modification of the ligand corresponds to drastic drop of
stereoselectivity.• Et3Al2Cl3 is highly pyroforic.
Wilke, G. Angew. Chem., Int. Ed. 1988, 27, 185. Wilke, G.; Monkiewciz, J.; Kuhn, H., US Patent, 4912274, 1990.
NiCl
ClNi
(1 atm)
(0.05 mol%)
Et3Al2Cl3 (0.15 mol%)PR3* (0.05 mol%)
-60 °C, 2.5 h, DCM 97% yield, 93% ee
NiCl
ClNi
(1 atm)
(1.2 mol%)
Et3Al2Cl3 (1.2 mol%)PR3* (1.2 mol%)
-70 °C, 2.5 h, DCM 35% yield, 92% ee
Facts on Nickel catalyzed hydrovinylation
• Diminished reactivity of electron-deficient vinyl arenes
• The apparent poor reactivity of substrates carrying heteroatoms when R2Al-X Lewis acids are employed that could be the result of coordination of these atoms to aluminium
• The desactivating effect of coordinating solvents (DCM<C6H5F<C6H5Cl<toluene<nitrobenzene<Et2O)
• The isomerisation of the initially formed 3-arylbut-1-ene to
2-arylbut-2-ene
• The total inhibition of the reaction by strong σ-chelating phosphines (or bisphosphines) Kawata, N.; Maruya, K.; Mizoroki, T.; Ozaki, A. Bull. Chem. Soc. Jpn. 1974, 47, 413.
Müller, U.; Keim, W.; Krüger, C.; Betz, P. Angew. Chem., Int. Ed. 1989, 28, 1011.Nomura, N.; Jin, J.; Park, H.; RajanBabu, T. V. J. Am. Chem. Soc. 1998, 120, 459.
(50 atm)
Ni(cod)2 (0.02 mol%)
L (0.02 mol%), Tol., 50 °C
Oligomerization(C4-C30)
OH
PPh2
F3C
F3CL =
Ni(cod)2
OH
PPh2
F3C
F3CPCy3, toluene
10 °C
O
P
F3C
F3C Ni
Ph Ph
PCy3
H
Ni(cod)2
OH
PPh2
F3C
F3C
i) ethylene, toluene-20 °C
ii) PCy3, -20 °C
O
P
F3C
F3C Ni
Ph Ph
PCy3 20 °C
-ethylene
A
A
Possible implication of a nickel hydride intermediate
Müller, U.; Keim, W.; Krüger, C.; Betz, P. Angew. Chem., Int. Ed. 1989, 28, 1011.
Proposed catalytic cycle (Part 1)
NiX
XNi
X = Br, Cl
PR3Ni
X
PR3
16 é complex(no coordination site)
Lewis acidNi
PR3
Y
14 é complex
Y = Lewis acid/Xcomplex
R
NiPR3
RNi
PR3
R
NiPR3
Y YY
H H
NiPR3
H
Y
Active catalyst
Nomura, N.; Jin, J.; Park, H.; RajanBabu, T. V. J. Am. Chem. Soc. 1998, 120, 459.RajanBabu, T. V. Chem. Rev. 2003, 103, 2845.
Proposed catalytic cycle (Part 2)
Nomura, N.; Jin, J.; Park, H.; RajanBabu, T. V. J. Am. Chem. Soc. 1998, 120, 459.RajanBabu, T. V. Chem. Rev. 2003, 103, 2845.
Me NiPR3
Y*NiPR3
Y
Me
Ph
NiPR3
H
Y
Active catalyst
Ph
NiPR3Me
Y
NiPR3
Y
Me
*
Me
*
Me
*
• Vary the ligands (phosphine)
• Replace the highly pyroforic Lewis acid in the previous catalytic cycle
• Use of silver salts or Brønsted acids with dissociated counter-ion
• Solvent effect (Lewis basicity…)
• Alternate metals? (Pd, Rh, Ru, Co…)
New propositions for the improvement of hydrovinylation reactions
PdCl
ClPd
PR3Pd
Cl
PR3
EtMgBr
Et2O
PdMe
PR3
Et2OH+BF4-
PdOEt2
PR3
BF4
DiRenzo, G. M.; White, P. S.; Brookhart, M. J. Am. Chem. Soc. 1996, 118, 6225.Nomura, N.; Jin, J.; Park, H.; RajanBabu, T. V. J. Am. Chem. Soc. 1998, 120, 459.RajanBabu, T. V.; Nomura, N.; Jin, J.; Nandi, M.; Park, H.; Sun, Y. J. Org. Chem. 2003, 68, 8431.
First efficient and «azaphosphalene-free » Ni-catalyzed heterodimerisation with ethylene
0.35 mol%[(allyl)NiBr]2/PPh3/AgOTf
DCM, -56 °C, 2 h(1 atm)
RR
Me
MeO Cl
Br Ph
F
MeO
>95% >95% >95% 81%
>95%
100% Selectivity
>95% 90% 90%
88%
Nomura, N.; Jin, J.; Park, H.; RajanBabu, T. V. J. Am. Chem. Soc. 1998, 120, 459.RajanBabu, T. V.; Nomura, N.; Jin, J.; Nandi, M.; Park, H.; Sun, Y. J. Org. Chem. 2003, 68, 8431.
First efficient and «azaphosphalene-free » Ni-catalyzed heterodimerisation with propene
Me[(allyl)NiBr]2 1.5 mol%
PPh3, AgOTf, DCMTemperature, Time
A B
Entry R Temp (°C) Time (min) Yield (%) Ratio (A:B)
1
2
3
4
5
6
7
8
RR R
i-Bu
OMe
Bz
NTs2
MVN
-15
-15
0
0
-40
10
10
-5
15
60
15
10
30
15
20
60
96
86
94
95
98
94
92
88
3:1
4:1
4:1
4:1
5:1
4:1
2:1
10:1
Cl
Br
OAc
Jin, J.; RajanBabu, T. V. Tetrahedron 2000, 56, 2145.
First efficient and «azaphosphalene-free » Ni-catalyzed heterodimerisation with norbornene
Kumareswaran, R.; Nandi, N.; RajanBabu, T. V. Org. Lett. 2003, 5, 4345.Park, H.; Kumareswaran, R.; RajanBabu, T. V. Tetrahedron 2005, 61, 6352.
"PR3-Ni-H"
+norbornene
+ethylene
Ni
PR3
NiL
PR3
"PR3-Ni-H"
(>99% Yield andSelectivity when
PR3 = PCy3)
Ni
PR3
+ethylene Ni
PR3
NiL
PR3
"PR3-Ni-H"
(>97% Yield andSelectivity when
PR3 = PPh3)
Possible asymmetric version of the heterodimerisation? 0.35 mol%
[(allyl)NiBr]2/AgOTfDiphosphine
DCM, -56 °C, 2 h(1 atm)
No reaction
PPh2Ph2PPPh2
PPh2O
OMe
Me
PPh2
PPh2N
CO2t-Bu
Ph2P
PPh2
BPPM (Achiwa)DIOP (Kagan)BINAP (Noyori)DPPP
PdI
IPd
*PR3Pd
I
*PR3
AgX
X = PF6 or SbF6
Pd*PR3
X
Pt-Bu O(-)-menthylP
Cy Ph
Ph
(10 atm)
[(allyl)PdI]2 0.2 mol%
AgSbF6, P*, 20 mL CH2Cl23 mL EtOAc(20 mL)
Ph *
+
Ph
79% yield84% Selectivity
86% ee
Possible asymmetric version of the heterodimerisation?
Bayersdörfer, R.; Ganter, B.; Englert, U.; Keim, W.; Vogt, D. J. Organomet. Chem. 1998, 552, 187.
0.35 mol%[(allyl)NiBr]2/AgOTf
Diphosphine
DCM, -56 °C, 2 h(1 atm)
No reaction
PPh2Ph2PPPh2
PPh2O
OMe
Me
PPh2
PPh2N
CO2t-Bu
Ph2P
PPh2
BPPM (Achiwa)DIOP (Kagan)BINAP (Noyori)DPPP
PdI
IPd
*PR3Pd
I
*PR3
AgX
X = PF6 or SbF6
Pd*PR3
X
Pt-Bu
PhO(-)-menthylP
CyBn
Ph
Ph
(10 atm)
[(allyl)PdI]2 0.2 mol%
AgSbF6, P*, 20 mL CH2Cl23 mL EtOAc(20 mL)
Ph *
+
Ph
79% yield84% Selectivity
86% ee
Use of hemilabile ligands for the asymmetric version of the heterodimerization
NiX
XNi
X = Br, Cl
NiX
P
16 é complex(no coordination site)
Lewis acidNi
P
16 é complex
Y = Lewis acid/Xcomplex
R
NiP
R
NiP
Y
H H
Active catalyst
P Z
Z
ZY
Z
If Z = PR3
not in equilibrium
ZY
NiP
HZ
Y
Nomura, N.; Jin, J.; Park, H.; RajanBabu, T. V. J. Am. Chem. Soc. 1998, 120, 459.RajanBabu, T. V.; Nomura, N.; Jin, J.; Nandi, M.; Park, H.; Sun, Y. J. Org. Chem. 2003, 68, 8431.
Use of hemilabile ligands for the asymmetric version of the heterodimerization
Nomura, N.; Jin, J.; Park, H.; RajanBabu, T. V. J. Am. Chem. Soc. 1998, 120, 459.Uozumi, Y.; Tanahashi, A.; Lee, S.-Y.; Hayashi, T. J. Org. Chem. 1993, 58, 1945.RajanBabu, T. V.; Nomura, N.; Jin, J.; Radetich, B.; Park, H.; Nandy, M. Chem. Eur. J. 1999, 5, 1693.
MeO(1 atm)(MVN)
0.7 mol% [(allyl)NiBr]2
M-X, (S)-MOP, DCMMeO
OMe
PPh2
AgOTf
24% Yield>99% Selectivity
58% ee
OMe
PPh2
NaBARF
>98% Yield>99% Selectivity
62% ee
BARF = -B[(3,5-CF3)C6H3]4
OBn
PPh2
NaBARF
93% Yield>99% Selectivity
80% ee
PPh2
NaBARF
13% Yield>99% Selectivity
3% ee
Use of hemilabile ligands for the asymmetric version of the heterodimerization
Nomura, N.; Jin, J.; Park, H.; RajanBabu, T. V. J. Am. Chem. Soc. 1998, 120, 459.Uozumi, Y.; Tanahashi, A.; Lee, S.-Y.; Hayashi, T. J. Org. Chem. 1993, 58, 1945.RajanBabu, T. V.; Nomura, N.; Jin, J.; Radetich, B.; Park, H.; Nandy, M. Chem. Eur. J. 1999, 5, 1693
MeO(1 atm)(MVN)
0.7 mol% [(allyl)NiBr]2
M-X, (S)-MOP, DCMMeO
OMe
PPh2
AgOTf
24% Yield>99% Selectivity
58% ee
OMe
PPh2
NaBARF
>98% Yield>99% Selectivity
62% ee
BARF = -B[(3,5-CF3)C6H3]4
OBn
PPh2
NaBARF
93% Yield>99% Selectivity
80% ee
PPh2
NaBARF
13% Yield>99% Selectivity
3% ee
A working hypothetical TS for the addition of nickel hydride to the vinyl arene
RajanBabu,T.V .; Nomura, N.; Jin, J.; Nandi, M.; Park, H.; Sun, X. J. Org. Chem. 2003, 68, 8431.Josef, J.; RajanBabu, T. V.; Jemmis, E. D. Organometallics 2009, 28, 3552.
Is the hemilabile ligation hypothesis a viable theory?• Minimalist construction of a hemilable model based
on chiral Me-DuPhos was necessary to probe the reactivity/selectivity of hydrovinylation.
Nandi, M.; Jin, J.; RajanBabu, T. V. J. Am. Chem. Soc. 1999, 121, 9899.Burk, M. J.; Feaster, J. E.; Harlow, R. L. Tetrahedron: Asymmetry 1991, 2, 569.
P
P
(S,S)-MeDuPhos
P
R
R
Size of thegroup
Tunabletether
Hemilabileatom
P NiO
RH
cis-olefin/P-complex
vs P NiO
RH
Ar
H
Effect of additional chiral centers
trans-olefin/P-complex
vs
Ar
HP Ni
OR
HH
Ar
Synthesis of various chiral phospholanes
X
Br
HP(O)(OEt)2, Pd(OAc)2, dppbDIEPA/DMSO
100 °C, 12 h
X
P
O
OEtOEt
X
PH2
LAH, Et2O
3 h, reflux
OOS
O O
KH, THF, 6 h
X
P
Me
Me
P
H
Me
Me
P
OBn
Me
Me
P
Me
Me
P
Me
Me
OBn OMe
Nandi, M.; Jin, J.; RajanBabu, T. V. J. Am. Chem. Soc. 1999, 121, 9899.
Synthesis of various chiral phospholanes
Nandi, M.; Jin, J.; RajanBabu, T. V. J. Am. Chem. Soc. 1999, 121, 9899.
X
Br
HP(O)(OEt)2, Pd(OAc)2, dppbDIEPA/DMSO
100 °C, 12 h
X
P
O
OEtOEt
X
PH2
LAH, Et2O
3 h, reflux
OOS
O O
KH, THF, 6 h
X
P
Me
Me
P
H
Me
Me
P
OBn
Me
Me
P
Me
Me
P
Me
Me
OBn OMe
A B
Effect of counterions and hemilability « potential »
Nandi, M.; Jin, J.; RajanBabu, T. V. J. Am. Chem. Soc. 1999, 121, 9899.
P
H
Me
Me
P
Me
Me
OBn
A B
Ph
[(allyl)NiBr]2 0.75 mol%Phosphine
Additive, CH2Cl2, -45 °C(1 atm) Ph *
vs
Entry AdditiveYield with
A (%)Yield with
B (%)Comments
1
2
3
4
5
AgOTf
AgClO4
AgNTf2
AgSbF6
NaBARF
94
95
<2
<2
<2
<2
<2
48
94
97
37% ee with A
37% ee with A
48% ee with B
50% ee with B
47% ee with B9% isomerisation
Hemilabile ligands containing a chiral 1,3-dioxolane
Zhang, A.; RajanBabu, T. V. Org. Lett. 2004, 6, 1515.
[(allyl)NiBr]2 0.75 mol%Phosphine
NaBARF, CH2Cl2, -45 °C(1 atm)
*
Ligand Conversion (%) Selectivity (%) ee (%)
P
OBn
R
R
P
St-Bu
Me
Me
P
Me
Me
O
O
R = Et
R = i-Bu
0 0 0
0 0 0
>95 >95 67
>95 >95 85
Hemilabile ligands containing a chiral 1,3-dioxolane
Zhang, A.; RajanBabu, T. V. Org. Lett. 2004, 6, 1515.
[(allyl)NiBr]2 0.75 mol%Phosphine
NaBARF, CH2Cl2, -45 °C(1 atm)
*
Ligand Conversion (%) Selectivity (%) ee (%)
P
R
R = Me
R = Et
>99 90 71
83 >95 88
>95 >95 91
>95 >95 90
O
O
P
O
O
P
O
O
Application of the hemilabile ligand in total synthesis
Zhang, A.; RajanBabu, T. V. Org. Lett. 2004, 6, 3159.
[(allyl)NiBr]2 0.70 mol%NaBARF, CH2Cl2, -55 °C, 2 h
Phosphine(1 atm)
MeMe
P
O
O
>99, 87% ee
1) 9-BBN (1.2 equiv)THF, 0 °C to rt
Pd(PPh3)4, K3PO4, 60 °CTHF/Dioxane, 14 h
Br2)
Me
55% over 2 steps(R)-(-)-Curcumene
Me
87% ee
1) HB(Siam)2, THF0 °C to rt
2) NaOH, H2O2
0 °C to rt Me
OH
Me
O
1) Swern oxidation2) THF, -78 °C to rt
3) Swern oxidation
BrMg
84%31% over 3 steps
(R)-(-)-ar-tumerone
Is the modified chiral MeDuPhos catalyst a better system?
Zhang, A.; RajanBabu, T. V. Org. Lett. 2004, 6, 3159.
[(allyl)NiBr]2 0.70 mol%NaBARF, CH2Cl2, -55 °C, 2 h
Phosphine(1 atm)
P
O
O
R
R
>100% Selectivity>95% yield
88% ee 87% ee 71% ee
73% ee 73% ee
MeOMeO
Me Br
Sugar phosphinite ligands used in hydrovinylation
[(allyl)NiBr]2 0.7 mol%NaBAr4, DCM
-50 °C or -70 °C
Diarylphosphinite L*(1 atm)
*
OPAr2
O
O
O
O
O
Ar2PO
OO
OPh
OMeNHAc
OAr2P
OO
OPh
OBnNH
OAc
Ar2P
OO
OPh
OBnNH
OTFA
Ar2P
OO
OPh
OBnNH
OBz
Ar2P
98% Conversion86% Yield
86% Selectivity<5% ee
68% Conversion68% Yield
99% Selectivity29% ee
62% Conversion62% Yield
99% Selectivity32% ee
99% Conversion23% Yield
23% Selectivity82% ee
99% Conversion40% Yield
40% Selectivity87% ee
99% Conversion89% Yield
89% Selectivity81% ee
Ar = 3,5-(CF3)2C6H3 Ar = 3,5-(CF3)2C6H3 Ar = 3,5-Me2C6H3
Ar = 3,5-Me2C6H3Ar = 3,5-Me2C6H3Ar = 3,5-Me2C6H3
Park, H.; RajanBabu, T. V. J. Am. Chem. Soc. 2002, 124, 734.Park, H.; Kumareswaran, R.; RajanBabu, T. V. Tetrahedron 2005, 6352.
Sugar phosphinite ligands used in hydrovinylation
Park, H.; RajanBabu, T. V. J. Am. Chem. Soc. 2002, 124, 734.Park, H.; Kumareswaran, R.; RajanBabu, T. V. Tetrahedron 2005, 6352.
[(allyl)NiBr]2 0.7 mol%NaBAr4, DCM
-50 °C or -70 °C
Diarylphosphinite L*(1 atm)
*
OPAr2
O
O
O
O
O
Ar2PO
OO
OPh
OMeNHAc
OAr2P
OO
OPh
OBnNH
OAc
Ar2P
OO
OPh
OBnNH
OTFA
Ar2P
OO
OPh
OBnNH
OBz
Ar2P
98% Conversion86% Yield
86% Selectivity<5% ee
68% Conversion68% Yield
99% Selectivity29% ee
62% Conversion62% Yield
99% Selectivity32% ee
99% Conversion23% Yield
23% Selectivity82% ee
99% Conversion40% Yield
40% Selectivity87% ee
99% Conversion89% Yield
89% Selectivity81% ee
Ar = 3,5-(CF3)2C6H3 Ar = 3,5-(CF3)2C6H3 Ar = 3,5-Me2C6H3
Ar = 3,5-Me2C6H3Ar = 3,5-Me2C6H3Ar = 3,5-Me2C6H3
Synthesis of enantioenriched (R)-Ibuprofene
Park, H.; RajanBabu, T. V. J. Am. Chem. Soc. 2002, 124, 734.Park, H.; Kumareswaran, R.; RajanBabu, T. V. Tetrahedron 2005, 6352.
[(allyl)NiBr]2 (0.7 mol%)AgSbF6, DCM, -70 °C
Diarylphosphinite L*(1 atm)
OO
OPh
OBnNH
OAc
Ar2P
Ar = 3,5-Me2C6H3
Br
98% Yield>99% Selectivity
89% ee
Br
NiCl2(dppp) (1.6 mol%)
i-BuMgCl
95%
O
O3, MeOHthen DMS
96%
OHO
KMnO4, Acetone
(R)-Ibuprofene66%
(-)-mentholDCC, DMAP
O(-)-menthyl-O
89% ee byGC analysis
Leitner’s study with Feringa phosphoramidite ligands
Franciό, G.; Faraone, F.; Leitner, W. J. Am. Chem. Soc. 2002, 124, 736.Hölscher, M.; Franciό, G.; Leitner, W. Organometallics 2004, 23, 5606.
Br
Cl
28.4% Conv.28.4% Selectivity
67.7% ee
83.4% Conv.98.8% Selectivity
91.9% ee
100% Conv.81.2% Selectivity
90.8% ee
(variable pressure)
[(allyl)NiCl]2NaBARF, DCM
TemperatureLigand
*
LigandQty Ligand
(mol%)Temp. (°C)
Selectivity (%) ee (%)Conv. (%)
N
Bu
PO
O
MeO
N
Bu
PO
O
Cl
N
Bu
PO
O
Cl
MeN
Ph
PO
O
Ph
Me
0.35
0.33
0.33
0.160.0210.00750.075
-30
-32
-32
-70-650
-50
13
100
33
1008910099.5
93.3
0%
96.2
84.910078.199.1
56.4
0% (Polym.)
87.2
94.891.176.289.7
Phosphoramidite screening and scope expansion done by RajanBabu
Smith, C. R.; RajanBabu, T. V. Org. Lett. 2008, 10, 1657.
O
O
P N
Ph
Ph
O
O
P N
Ph
Ph
O
O
P N
Ph
MeO (1 atm)
[(allyl)NiBr]2 0.7 mol%NaBF4, CH2Cl2, -78 °C
PhosphoramiditeMeO
*
O
O
P N
Ph
O
O
P N
Ph
Ph O
O
P N
Ph
PhO
O
P N
1-naphthyl
Ph
>99% Conv.>99% Selec.
94% ee
>99% Conv.>99% Selec.
94% eeNo reaction
21% Conv.>99% Selec.
90% ee
14% Conv.>99% Selec.
16% ee
2% Conv.>99% Selec.
86% ee
>99% Conv.>99% Selec.
98% ee
Phosphoramidite screening and scope expansion done by RajanBabu
Smith, C. R.; RajanBabu, T. V. Org. Lett. 2008, 10, 1657.
O
O
P N
Ph
Ph
O
O
P N
Ph
Ph
O
O
P N
Ph
MeO (1 atm)
[(allyl)NiBr]2 0.7 mol%NaBF4, CH2Cl2, -78 °C
PhosphoramiditeMeO
*
O
O
P N
Ph
O
O
P N
Ph
Ph O
O
P N
Ph
PhO
O
P N
1-naphthyl
Ph
>99% Conv.>99% Selec.
94% ee
>99% Conv.>99% Selec.
94% eeNo reaction
21% Conv.>99% Selec.
90% ee
14% Conv.>99% Selec.
16% ee
2% Conv.>99% Selec.
86% ee
>99% Conv.>99% Selec.
98% ee
Phosphoramidite screening and scope expansion done by RajanBabu
Smith, C. R.; RajanBabu, T. V. Org. Lett. 2008, 10, 1657.Smith, C. R.; RajanBabu, T. V. J. Org. Chem. 2009, 74, 3066.
(1 atm)[(allyl)NiBr]2 0.7 mol%NaBF4, CH2Cl2, -78 °C
*
O
OP N
Ph
1-naphthyl
R R
MeO i-Bu Ph
MeO
F
PhO
77% Yield>99% Selectivity
97% ee
97% Yield>99% Selectivity
96% ee
92% Yield>99% Selectivity
97% ee
98% Yield>99% Selectivity
99% ee
92% Yield>99% Selectivity
97% ee
• DCM was added to a purged Schlenk flask with N2, and put in the glove-box.
• Mix [(allyl)NiBr]2, phosphoramidite and NaBARF in Schlenk. Stir for 2 hrs at rt.
• Suspension is filtered on a celite pad and transferred to another Schlenk flask and tanken out of glove-box.
• To another flamed dried flask, add DCM and transfer pre-catalyst dropwise at rt. Cool this solution at -70 °C.
• Purge with ethylene. Add the styrene derivative dropwise in DCM. Re-purge with ethylene and react for 4-6 hrs.
• Quench by adding to pentane and filter on silica gel plug.
Typical procedure for the hydrovinylation of styrene derivatives
Smith, C. R.; Zhang, A.; Mans, D.; RajanBabu, T. V. Org. Synth. 2008, 85, 238.
Enantioselective formation of quaternary carbon centers by hydrovinylation
Zhang, A.; RajanBabu, T. V. J. Am. Chem. Soc. 2006, 126, 5620.Shi, W.-J.; Zhang, Q.; Xie, J.-H.; Zhu, S.-F.; Hou, G.-H.; Zhou, Q.-L. J. Am. Chem. Soc. 2006, 2780.Smith, C. R.; Lim, H. J.; Zhang, A.; RajanBabu, T. V. Synthesis 2009, 2089.
OO
P
NPh
Ph
Yields 76% to 96%Selectivity 84% to 89%
ee 70% to 99%
(1 atm)[(allyl)NiBr]2 1.0 mol%NaBF4, CH2Cl2, -70 °C
O
OP N
Ph
Ph
R R
Me
95% Yield>99% Selectivity
95% ee
R'
Me
R'
Me
90% Yield>99% Selectivity
90% ee
Me
Me
90% Yield95% Selectivity
90% ee
Cl
Me
60% Yield>97% Selectivity
95% ee
Me
93% Yield>96% Selectivity
50% ee
Me
98% Yield>99% Selectivity
93% ee
Me
70% Yield71% Selectivity
95% ee
In comparison…
Takemoto, T.; Sodeoka, M.; Sasai, H.; Shibasaki, M. J. Am. Chem. Soc. 1994, 115, 8477Hulme, A. N.; Henry, S. S.; Meyers, A. I. J. Org. Chem. 1995, 60, 1265.Fadel, A.; Azrel, P. Tetrahedron: Asymmetry 1997, 8, 371.
HON Me
Me
H
(+)-eptacozine
HOMe
H
N Me
(+)-aphanorphine
MeO
Shibasaki
Meyers
Me
MeO OTf
Me
OTBDPSAsymmetric Heck reaction
(93% ee)
MeO
NO
i-Pr
Stoichiometric oxazoline alkylation(99% ee)
Enzyme mediated desymmetrisation of chiral malonate (97% ee)
MeOMe
CO2Me
CO2Me
Catalytic hydrovinylation of 1,3-dienes
Zhang, A.; RajanBabu, T. V. J. Am. Chem. Soc. 2006, 128, 54.Buono, G.; Siv, C.; Peiffer, G.; Triantaphylides, C.; Denis, P.; Mortreux, A.; Petit, F. J. Org. Chem. 1985, 50, 1781.RajanBabu, T. V. Synlett 2009, 853.
t-Bu[(allyl)NiBr]2 7.0 mol%
PPh3, AgOTf
-56 °C, DCM(1 atm)
no reaction(~20% Conv. at rt)
t-Bu[(allyl)NiBr]2 0.14 mol%
NaBARF, L*
-70 °C, DCM(1 atm) PPh2
OBnn
t-Bu t-Bu
With n = 099% Yield
98% Regioselectivity2:1 dr
0.45 mol%Ni(cod)2, Et2AlCl, P*
0 °C, toluene
OPPh2
OPPh2
NPPh2Me
AMPPQuant. 93% ee
? Selectivity
Catalytic hydrovinylation of 1,3-dienes
Zhang, A.; RajanBabu, T. V. J. Am. Chem. Soc. 2006, 128, 54.RajanBabu, T. V. Synlett 2009, 853.
[(allyl)NiBr]2 0.14 mol%NaBARF, L*
-70 °C, DCM(1 atm)
PPh2
OBn
BnO
OBn
OPh MeO2C
94% Conversion>99% Regioselect.
>99% Conversion68% Regioselect.
>99% Conversion72% Regioselect.
>99% Conversion>99% Regioselect.
>99% Conversion98% Regioselect.
97% Conversion>99% Regioselect.
>99% Conversion95% Regioselect.
>99% Conversion98% Regioselect.
Asymmetric calatysis : comparison with the previous MeDuPhos chiral hemilabile system
O
Ph
Substrate
P
O
O
O
OP N
Ph
Ph
Conv.(%) Select. (%) ee (%) Conv.(%) Select. (%) ee (%)
>99
>99
>99
88
>99
97
>99
>99
85
93
38
<5
>99
>99
>99
0
>99
>99
>99
0
96
99
95
0
Zhang, A.; RajanBabu, T. V. J. Am. Chem. Soc. 2006, 128, 54.RajanBabu, T. V. Synlett 2009, 853.
Is the Feringa’s ligand the way to catalyze hydrovinylation with every substrate?
Bu Many products
Ph
(1 atm)
[(allyl)NiBr]2 1 mol%
NaBARF, DCM, -70 °CPh
Me
99%, 80% ee
O
OP N
Ph
Ph
(1 atm)
[(allyl)NiBr]2 1 mol%
NaBARF, DCM, -70 °C
O
OP N
Ph
Ph
Smith, C. R.; RajanBabu, T. V. Org. Lett. 2008, 10, 1657.Smith, C. R.; RajanBabu, T. V. J. Org. Chem. 2009, 74, 3066.
Colbalt-catalyzed hydrovinylation of unactivated dienes
Sharma, R. K.; RajanBabu, T. V. J. Am. Chem. Soc. 2010, 132, 3295.Grutters, M. M. P.; Müller, C.; Vogt, D. J. Am. Chem. Soc. 2006, 128, 7414.
R
CoCl2 (5 mol%)dppb (5 mol%),
Me3Al (15 mol%)
DCM:toluene (4:1), Temp (°C)(1 atm)
R R
RR
PPh2Ph2P
A B
C D
R Temp. (°C) P PA (%) B (%) C (%) D (%)
n-Pentyl
n-Pentyl
n-Pentyl
n-Pentyl
n-Pentyl
n-Hexyl
n-Heptyl
n-Octyl
n-Methyl
BnO(CH2)2
-10
-20
-10
-20
-10
-10
-10
-10
-10
0
dppb
dppm
dppe
dppp
2 PPh3
dppb
dppb
dppb
dppb
dppb
93
<2
70
75
0
93
95
95
95
78
7
30
0
0
0
7
0
0
1
0
0
67
0
0
0
0
0
0
0
0
0
<2
10
14
0
0
<2
<2
0
0
Catalytic cycle (Part 1)
Sharma, R. K.; RajanBabu, T. V. J. Am. Chem. Soc. 2010, 132, 3295.
CoCl
Cl
R
R
Active catalyst
CoP
HP
Me2AlCl2
P
P
Me3Al Me2AlCl
CoCl
Me
P
P
Me2AlCl Me2AlCl2
Co MeP
P
Me2AlCl2
CoMeP
P
R
Me2AlCl2
CoP
P
Me2AlCl2R
MeMe
Catalytic cycle (Part 2)
Sharma, R. K.; RajanBabu, T. V. J. Am. Chem. Soc. 2010, 132, 3295.
Active catalyst
CoP
HP
Me2AlCl2R
CoP
PH
R
CoP
P
R
CoP
P
R
CoP
P
R
Me
R
Me
A
Asymmetric version using Kagan’s DIOPV (or BDPP)
Sharma, R. K.; RajanBabu, T. V. J. Am. Chem. Soc. 2010, 132, 3295.
O
O
PPh2
PPh2
(R,R)-DIOP
PPh2
PPh2
(S,S)-BDPP
R
CoCl2 (5 mol%)dppb (5 mol%),
Me3Al (15 mol%)
DCM:toluene (4:1) -45 °C, 6 h
(1 atm) R
R P P yield (%) ee (%)
n-Pentyl
n-Pentyl
n-Hexyl
n-Heptyl
n-Octyl
Methyl
BnO(CH2)2
BnO(CH2)2
(R,R)-DIOP
(S,S)-BDPP
(R,R)-DIOP
(R,R)-DIOP
(R,R)-DIOP
(R,R)-DIOP
(R,R)-DIOP
(S,S)-DIOP
95
96
96
98
95
90
40
40
95
97
95
95
96
90
99
96
Ph
Me(S,S)-BDPP 99 <5%
Recent developpements in heterodimerisation reactions : Iron catalyzed reaction (T. Ritter)
Moreau, B.; Wu, J. Y.; Ritter, T. Org. Lett. 2009, 11, 337.
R1
R2
R3+ R1
R2
R3
Me
NN Ph
X
2 mol%Pyridine + FeCl2
Mg (4 mol%), Et2O
Me
Me
Me
t-BuMe
Me
Me
AcO
X = Me or CH2TMS
Me
Me
F
Both alkenes are (E)at >99:1
Me
MeO
Me
MePh
Me
Me
Me
Ph
Me
92% 85%74%
91:9 Regioselectivity
51%96:4 Regioselectivity
77%98:2 Regioselectivity
79%
Recent developpements in heterodimerisation reactions : Iron catalyzed reaction (T. Ritter)
Moreau, B.; Wu, J. Y.; Ritter, T. Org. Lett. 2009, 11, 337.
NFe
Cl
Cl
N
Me
Mg(0) NFe
N
Me
PhHE
Hz NFe
N
Me
Ph
FePh
HzHE
Me
NN
H
PhFe
Hz
HE
Me NN
Ph Me
HE
FeHZ
N N
Me
Ph Me
HE
Hz
Recent developpements in heterodimerisation reactions : branched-branched coupling
Ho, C.-Y.; He, L. Angew. Chem., Int Ed. 2010, 49, ASAP.Ho, C.-Y.; Jamison, T. F. Angew. Chem., Int. Ed. 2007, 46, 782
Ar R
N N
Ni i-Pr
i-Pr
i-Pr
i-Pr
HTfO
Toluene, rt
"generated in situ"
5 mol%
ArR
In situ conditions:
5 mol% Ni(cod)25 mol% IPr
1-octeneTESOTf, Et3N
MeO
O ONi
Arn-hexyl
H
TfOIPrTES
Arn-hexyl
OTES
N N
Ni i-Pr
i-Pr
i-Pr
i-Pr
HTfO
Recent developpements in heterodimerisation reactions : branched-branched coupling
Ho, C.-Y.; He, L. Angew. Chem., Int Ed. 2010, 49, ASAP.Ho, C.-Y.; Jamison, T. F. Angew. Chem., Int. Ed. 2007, 46, 782
Ar R
N N
Ni i-Pr
i-Pr
i-Pr
i-Pr
HTfO
Toluene, rt
"generated in situ"
5 mol%
ArR
Me Me MeMe
MeOAcO
Me Me Me
Ph
Me
Ph
Et
MeO
91%86% Hetero.
92%89% Hetero.
90%88% Hetero.
68%94% Hetero.
72%69% Hetero.
90%87% Hetero.
81%87% Hetero.
92%95% Hetero.
77%>99% Hetero.
5555
Recent developpements in heterodimerisation reactions : branched-branched coupling
Ho, C.-Y.; He, L. Angew. Chem., Int Ed. 2010, 49, ASAP.Ho, C.-Y.; Jamison, T. F. Angew. Chem., Int. Ed. 2007, 46, 782
IPr
NiTfO H
IPr
NiTfO
Ar
Ar
R
IPr
NiTfO
HAr
R
IPr
NiTfO
HAr
R
vs
IPr
NiTfO
H
R
Ar
ArR
• New chemistry for the incorportation of an « ethylene » unit on activated and non-activated olefins Highly catalytic reaction amenable to asymmetric
synthesis
• These methodologies are now ready to be applied to the synthesis of more complex natural molecules
• Broadly applicable control elements to improve selectivity of useful organic transformations Tunable hemilabile ligands Counter-ion effects Acyclic stereocontrol in diene chemistry
Conclusions
Don’t let ethylene ripen your fruits!
top related