Aldol reaction, 4-substituted-2,6-heptanediones, 5-substituted-3-methyl-2-cyclohexene-1-ones, (8α,9S)-6′-Methoxycinchonan-9-amine, Quinine Derivative

Aldol cyclodehydration of 4-substituted-2,6-heptanediones leads to enantiomerically enriched 5-substituted-3-methyl-2-cyclohexene-1-ones, which serve as perfume ingredients and valuable synthetic building blocks. Primary amines derived from cinchona alkaloids in combination with acetic acid are efficient catalysts for this transformation, which deliver both enantiomers of the celery ketone.