Enantioselective synthesis of both enantiomers of methyl dihydrojasmonate using solid-liquid asymmetric phase-transfer catalysis

[GRAPHICS] Both enantiomers of methyl dihydrojasmonate (-)-1 and (+)-1 were obtained b y a short route using asymmetric Michael addition of dimethyl malonate onto pentyl enone 3, followed by nonracemizing demethoxycarbonylation. The key enantioselective step involves a new system of asymmetric solid-liquid phas e-transfer catalysis using solvent-free conditions, Enantiomeric excess as high as 90% (91% yield) was achieved.