Problems 837
- Cindy Synthon tried to prepare the following compounds using aldol condensations. Which of these compounds was she successful
in synthesizing? Explain why the other syntheses were not successful.
a. d. g.
b. e. h.
c. f. i.
- Explain why the following bromoketone forms different bicyclic compounds under different reaction conditions:
- Explain why the product obtained in the following reactions depends on the number of equivalents of base used in the reaction:
- A Mannich reactionputs an group on the of a carbon acid. Propose a mechanism for the reaction.
O
CH 2 N
HCH
O
O
CH 3
HN CH 3
CH 3
CH 3
+ +
catalytic
H+
NCH 2 a-carbon
CH 3 CCH 2 COCH 2 CH 3
O O
CH 3 CCHCOCH 2 CH 3
O
CH 3
- CH 3 CH 2 O− O
one equivalent
- CH 3 Br
CH 3 CCH 2 COCH 2 CH 3
O O
CH 3 CH 2 CCH 2 COCH 2 CH 3
- CH 3 CH 2 O− O O
two equivalents
- CH 3 Br
- H 3 O+
25 °C
LDA
THF
− 78 °C
CH 3 O−
CH 3 OH
C
CH 3
CH 3
Br
O
C
O
O
O
CH 3 CCH 2 CH
CH 3
CCH
CH 3
CH CH^3
O
O
CH 2
CH 3
CCCH 2 CH 2 CH 3
O
CH 3 CCH
CH 3
CCH
CH 3
CH CH^3
2 CH 3
O
O
CH 3 CH
CH 3
CCH
CH
CH 3
O
O
CH 3 C
CH 3
CHCH
O
CH 2 CHCCH 3
