Help with Aldol Condensation - Organic Chemistry

Card 0 of 2

Question

Screen shot 2015 07 07 at 8.30.46 pm

Determine the major product of the given intramolecular aldol reaction.

Screen shot 2015 07 07 at 8.30.53 pm

Answer

Keep in mind the following principles: Cyclization is favored when a five/six-member ring may be formed. Addition at an aldehyde is favored relative to the same reaction at a ketone.

As a result, abstraction of a hydrogen bound to carbon 6 (an alpha-carbon) is favored since the resulting carbanion may attack the aldehyde (carbon 1) to form a six-member ring, resulting in compound II. Compound I results from abstracting a hydrogen from carbon 2, generating a carbanion which may then attack the ketone. Based on the latter of the above principles, this is a minor product.

Compare your answer with the correct one above

Question

What is the final organic product of the reaction shown?

Screen shot 2015 11 13 at 2.54.29 pm

Screen shot 2015 11 13 at 2.54.56 pm

Answer

First step: Friedel-Crafts acylation of benzene

Second step: Formation of enolate

Third step: aldol addition (enolate attacks carbonyl carbon in benzaldehyde)

Fourth step: neutralization of anion and dehydration forming alkene

Compare your answer with the correct one above

Tap the card to reveal the answer