Chemistry Reference
In-Depth Information
O
H
O
TMG (
1
) (20 mol%)
EtO
2
C
+
Me
2
S
+
Br
-
CO
2
Et
H
K
2
CO
3
(2 equiv)
MeCN aq
H
89%
Scheme 4.38
TMG (1) catalysed cyclopropanation through tandem Michael-displacement
reactions
Table 4.15
Two-step synthesis of vinyl halides from ketones through hydrazones
TBS
H
TBS
NN
O
X
N
step 2
H
TBS
N
H
R
2
R
2
R
1
R
1
R
2
cat.Sc(OTf)
3
R
1
R
1
R
2
Run
Step 2
Yield (%)
O
Me
) DCM, 23
C (X
1
Br
2
, BTMG (
2
¼
Br)
Br
O
MeO
) THF, 0
C
2
I
2
, TMG (
1
82 (X
¼
I)
MeO
Me
O
O
Br)
a
) DCM, 23
C (X
3
Br
2
, BTMG (
2
¼
Me
O
OH
O
I)
b
O
1
) THF, 0
C
¼
4
I
2
, TMG (
84 (X
N
OH
O
Me
I)
c
) THF, 0
C
5
I
2
, TMG (
1
71 (X
¼
MeO
a
gem-Dibromide was formed in 7% yield.
b
tetrasub.: trisub.
57 : 43.
c
terminal: inner-
E
: inner-Z
¼
¼
62 : 21 : 17.
