A new and feasible method for synthesizing optically active (R)- and (S)-(+)-a-curcumene (I) via 6-methyl-5-hepten-2-ylmagnesium bromide asym. cross-coupling reaction with p-bromotoluene catalyzed by chiral phosphine-transition metal complexes, in optical yield up to 50% e.e., was described. (R)-(-)-a-Curcumene was converted into (R)-(-)-b-curcumene (II) by Birch reduction (S)-(+)-g-Curcumene (III) was synthesized from p-bromophenylmethyl ether via asym. cross-coupling, Birch reduction etc.

Key words: CATALYST, HEPTENE P, GRIGNARD REAGENT, TRANSITION METAL COMPLEX, BENZENE P, SESQUITERPENE, ESSENCIAL OIL, PHOSPHINE, BROMOHYDROCARBON, CHIRALITY