Synthesis of α-damascone [trans-1-(2,6,6-trimethylcyclohex-2-enyl)but-2-en-1-one] by a catalysed Diels–Alder reaction with inverse electron demand

Abstract

The synthesis of α-damascone from isoprene, acetyl chloride, and 2-methylpropene is described. The catalysed addition of 2-methylpropene to 4-methylhexa-3,5-dien-2-one gave several products including the Diels–Alder adduct (4), which was converted into α-damascone by condensation with acetaldehyde.