Chemistry Reference
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CH(COOMe) 2
Nu
R
R
n
R
Nu-H
L
% Conv (time)
% ee
n
L
% Conv (time)
% ee
Ph
Ph
Me
CH 2 (COOMe) 2
BnNH 2
CH 2 (COOMe) 2
40a
40a
43h
100 (6 h)
60 (24 h)
88 (10 h)
99 ( S )
94 ( R )
89 ( R )
1
2
40a
40a
37 (36 h)
43 (36 h)
85 ( R )
92 ( R )
CH(COOMe) 2
CH(COOMe) 2
L
% Conv (time)
% regio
% ee
L
% Conv (time)
% ee
40c
100 (1 h)
80
90 ( S )
40a
80 (24 h)
91 ( S )
Figure 10.21 Summary of the best results obtained in the Pd-catalyzed allylic substitution of
several substrates using ligands 40-43.
R
O
% Yield
% ee
N
R
PPh 2
O
D- xylo
a
b
c
d
i Pr
Bn
CH 2 C 10 H 7
( R )-CH(CH 3 )Ph
67
64
75
17
46( S )
75( S )
49( S )
73( S )
O
O
44
Figure 10.22 Phosphine-oxazine ligands 44; and yields and enantioselectivities obtained with
them.
D- galacto
OR
D- gluco
D- gluco
OR
RO
O
O
RO
RO
PPh 2
AcO
AcO
PPh 2
O
X
PPh 2
N
N
X
RO
N
MeO
OR
OAc
OR
46 X= CH 2 ; R= Ac (45% ( S ))
47a X= O; R= H (0%)
47b X= O; R= Ac (0%)
45 (20% ( S ))
48a R= H (1% ( R ))
48b R= Ac (3% ( S ))
OAc
D- gluco
OAc
O
O
AcO
AcO
AcO
AcO
OMe
49a R= t Bu (87% ( S ))
49b R= Bn (82% ( S ))
D- gluco
OR
HN
N
OMe
BnO
BnO
Ph 2 P
50 (71% ( S ))
49c R=
Ph 2 P
(86% ( S ))
O
OBn
Figure 10.23 Phosphine-imine 45-49 and phosphine-amine 50 ligands; and enantioselectivi-
ties obtained with them in the Pd-allylic alkylation of 1,3-diphenylprop-2-enyl acetate.
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