Question #95aae

1 Answer
Jul 3, 2015

This is an intramolecular base-catalyzed aldol condensation.


The structure of cyclodecane-1,6-dione is usually written as

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But the mechanism will make more sense if we write it as

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(1) The base removes an α-proton from C-10 (to the left of the top carbonyl group) to form an enolate ion.

(2) The carbanion at C-10 attacks the base of the carbonyl group at #"C-6"# to form an alkoxide ion, which gets protonated to form an aldol

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(3) The aldol is dehydrated under the basic conditions to form an α,β-unsaturated ketone (bicyclo[5.3.0]dec-1,7-en-2-one).

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