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Organic Reaction Mechanisms IV: Elimination
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E1cB mechanism
NEET level
Single correct option
Difficulty 1 of 3
o4132
The carbanion intermediate formed when an aldol loses water in basic medium is
A
a carbocation
B
an enolate ion
C
a free radical
D
a carbene
Answer: B
Removal of the alpha-H (next to
C
=
O
) gives a resonance-stabilised enolate, which is the carbanion intermediate of the E1cB dehydration.
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