Ph.D. Thesis_AS_Publishing version for IRC_12 ... - Jacobs University

Chapter 1
O
O
O
OH
H
(S)-proline (30 mol%)
R
DMSO/Acetone (4:1)
rt, 4hrs
R
R = NO 2
(68% yield, 76% ee)
Scheme 1.4. First example of a (S)-proline catalyzed asymmetric intermolecular aldol reaction.
O
OH
R
H
O
N
H O
H
A
O
R H
H
O
N
H
O
OH
O H
G
N
OH
B
H
O
O
H
+H 2 O
H
O
-H 2 O
N
O
H
O
H
N
H
O
O
R
N
H
O
O
R H
O
H
F
Si faceial attack not favored
C
Tautomerization
O
H O
H
R H
O
N
O
N
O
O
H
H
R
E
D
H
Scheme 1.5. Proposed enamine mechanism for intermolecular aldol reaction.
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