4- Acetylbutanoic acid

Chiral 4,4-disubstituted cyclohexenones.1 The chiral bicyclic lactam 2, obtained by reaction of 4-acetylbutanoic acid with 1, on dialkylation gives mainly the diastereomer from endo-attack, with the highest diastereoselectivity obtained by using the larger electrophile in the second alkylation. Hydride reduction followed by hydrolysis furnished 4,4-dialkylated cyclohexenones (4) in >95% ee. 

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