Ready; Catalysis Hydroformylation
Ready; Catalysis Hydroformylation
Ready; Catalysis Hydroformylation Asymmetric Hydroformylation: under-developed
OH
OH
4 stepshigh yield PPh2
OH
O
OPCl PPh2
O
O
PO
(S,R)-BINAPHOS
R
0.5-0.1 mo% Rh(acac)(CO)2BINAPHOS (4x [Rh])H2/CO (100 atm)
R
CHO
HayashiJOC, 1993, 1945
n:i selectivity "beyond the discussion here"Nozaki, JACS, 1997, 4413
R
Ph
4-OMe-Ph
4-ClPh
PivO
4-CF3-Ph
N
O
O
% ee i:n
92
88
93
93
93
85
88:12
87:13
87:13
96:4
88:12
89:11
O
CH3
CH3 O
CH3
CH3OHC
O
CH3
CH3
CH3H3C
O
OH
OH
HHO2C
(+)-Ambruticin Jacobsen, JACS, 2001, 10772
91:9 i:n96:4 d.r.
R
R'
R
R' CHO
*?
see Breit, Eur. JOC, 1998, 1123,Buchwald, JACS, 2011, 19080
Ready; Catalysis Hydroformylation
O 1. H2N-NH2
2. succinyl chloride,PH2
PH2
NN
PNN
P
O
O
O
OCO2H R
RR
R
~30%
(±)-
R = CO2H
A: R =O
NH
(resolve diastereomers)
R
500 psi H2/CORh(acac)CO2/A (0.02 mol%)
60 oC CHOR
CH3
CH3
CHO
30:1 b:l100% conv89% ee
CH3
CHO AcO
CH3
CHONC
4.8:1 b:l100% conv87% ee
40:1 b:l100% conv95% ee
Landis, Klosin, JACS, 2005, 5040Stahl, Landis, JACS, 2010, 14027
HN
CH3
CHO
33:1 b:l99% conv99% ee
BocHN
CH3
CHO
51:1 b:l99% conv94% ee
Cbz
CH3
CHO
2:1 b:l99% conv96% ee
TBSOCH3
CHO
4.4:1 b:l99% conv86% ee
BzCHNCH3
CHO
7:1 b:l99% conv93% ee
AcO
OAc
Ready; Catalysis Hydroformylation-4
Ready; Catalysis Hydroformylation
Ready; Catalysis Hydroformylation
Ready; Catalysis Hydrosilylation
Note in some cases X-Si bond formation precedes H-C bond formation
Hydrosilylation
What:R
H-SiR3
catalyst
RSiR3
OR ORSiR3
catalyst usually = Pt, Rh, Pd, Ir
why:R
SiR3 [O]R
OH
To retire rich, young and famous:
R ROH
R
OHorH2O+
H-OH 120C=C 60O-C -90C-H -100
!H ~ -10 kcal/molOR
SiR3 = protected alcohol
How: Mn
Mn+2
SiR3
H
Mn+2
SiR3
H
X
Mn+2
SiR3
X
H
XSiR3
H
HSiR3
X
or as adhesives, surfactants(major applications industrially)
Ready; Catalysis Hydrosilylation
Ready; Catalysis Hydrosilylation
Platinum [very active, Pt(II) - Pt(IV)]2007: 5.6 metric tons of platinum used for hydrosilylation
H2PtCl6 6H2O0.005 mol%MeCl2Si-H
H2PtCl6 6H2O0.5 mol%MeCl2Si-H
H2PtCl6 6H2O0.5 mol%MeCl2Si-H
SiCl2Me
93%
SiCl2Me
98%
SiCl2Me
Has been suggested that Pt colloids are the real catalyst. These are suspensions of fine particles 10-1000 A radius. These solutions appear homogeneous and are able to pass through filters.
quant.
BnO H
OSiMe2H
10 mol% HMDS2 mol% H2PtCl6 6H2O>80 %yield
BnO H
O SiMe2
8 stepsH
OO
OJatrophatrionePaquette, JACS, 2002, 6542
O
HOBn
OMeO
O
OH
1. (Me2HSi)2NH;H2PtCl62. TBAF
O
HOBn
OMeO
O
OH
87:13
54%
Leucascandrolide AKozmin, OL, 2001, 755
Ready; Catalysis Hydrosilylation
Ready; Catalysis Hydrosilylation
LnCu Cl
LnCu OtBu
H SiR3
LnCu OtBu
H SiR3
LnCu H
O
O
CuLn
H
OCuLn
H
tBuOSiR3
H SiR3
KOtBu
OSiR3
H
OMe
MeO
MeO
MeO
OO
O
ClMg Me
EtO2C(formed in situ from iodide) OMe
MeO
MeO
MeO
OO
O
O
MeO-BIPHEP, NaOtBu (1.2 equiv)PMHS, tBuOH>85%, 93%ee
OMe
MeO
MeO
MeO
OO
O
O
NaHMDS, MeI
OMe
MeO
MeO
MeO
OO
O
O CH3
Buchwald, ACIE, 2005, 6177
(±)-
Cu-Catalyzed Hydrosilylation: Mechanism and Application
Ready; Catalysis Hydrosilylation
Ready; Catalysis Hydrosilylation
Ready; Catalysis Hydrosilylation
Ready; Catalysis Hydrosilylation
Ready; Catalysis Hydrosilylation
Ready; Catalysis Hydrosilylation
Ready; Catalysis Hydrosilylation
BnO
OSi
H Rh(acac)(CO)2, CO; H2O2, KF, MeOH
BnO
OH O OH
1 pot, 3 stereocenters, 2 oxygens, 2 C-C bonds67%, 15:1 dr 6 steps
BnO
OTBS O O
O
OH
Rh(acac)(CO)2CO/H2
BnO
OTBS O O
O
O OH >94%
8 steps
OH OH OH
O OMe
O
H
OHJACS, 2011, 7308
Ready; Catalysis Hydrosilylation
Ready; Catalysis Hydrozirconation
Ready; Catalysis Hydrozirconation
Ready; Catalysis Hydrozirconation
Ready; Catalysis Hydrozirconation
Ready; Catalysis Hydroacylation
Ready; Catalysis Hydroacylation
Ready; Catalysis H-X Additions to Olefins