Chemistry Reference
In-Depth Information
R
2
O
R
2
O
Me
R
2
MgBr
CuBr•SMe
2
, Ligand
9
CH
2
Cl
2
-70
PPh
2
PCy
2
O
R
1
+
OEt
R
1
OEt
R
1
Main product
Fe
OEt
R
2
*
O
°
C,16h
+
9
(R,S)-reversed Josiphos
R
1
OEt
P
P
Br
Br
Cu
P
Cu
R
2
OMgBr
P
R
1
OEt
R
2
MgBr
R
2
Br
P
P
P
Br
III
R
2
Cu
MgBr
Cu
OMgBr
R
2
MgBr
O
R
1
OEt
R
1
OEt
P
Br
P
Br
P
MgBr
P
R
2
OMgBr
R
2
III
Cu
Cu
O
R
1
OEt
R
1
OEt
Scheme 8A.4.
A proposed catalytic cycle for the 1,6-asymmetric conjugate additions.
R
2
NMe
2
R
2
MgBr, CuBr·SMe
2
10,
CH
2
Cl
2
,-75
°
C
R
1
R
1
R
2
+
Br
R
1
87-99% Yield
92-98%
ee
PPh
2
R
1
= Ph, 1-Napht,
p
-Cl-Ph,
p
-CO
2
Me-Ph, BnOCH
2
R
2
= Me, Et,
Ph
2
P
10 Taniaphos
Fe
n
Bu,
()
n
Scheme 8A.5.
O
O
1.2 R
3
Mg Br, Et
2
O
3% CuOTf
2
,4%ImH
+
(11 or 12)
0
R
3
R
1
=Me,H
R
2
= Me, Et,
i
-Bu,
n-
Bu, Ph
R
3
=Me,Et
R
1
R
1
R
1
R
1
()
n
R
2
(
n
R
2
°
C, 30 min
46-82%
ee
H
BF
4
PF
6
OH
Ar
H
Ar
N
N
N
N
R
Ph Ph
11
:Ar = 1-Naphth
12
:R = tBu
Scheme 8A.6.
