Synthesis of (+)-α-curcumene, (+)-curcumone, and (-)-methyl citronellate starting from optically pure 5-trimethylsilyl-2-cyclohexenone

Abstract

1,4-Addition of Grignard reagents in the presence of chlorotrimethylsilane to 5-trimethylsilyl-2-cyclohexenone (1) proceeded in a highly diastereoselective manner to give trans adducts in high yields. (+)-(α-Curcumene, (+)-curcumone, and (-)-methyl citronellate were synthesized starting from optically pure 1.