Stereoselective first total synthesis of (4S)-trans-β-elemenone was achieved from (S)-2-cyclohexen-1-ol, prepared easily by the asymmetric reduction of 2-cyclohexen-1-one with chiral hydride reagent.
BF3-induced cyclobutane-opening of verbenone and its deconjugate homolog. Efficient preparation of o-mentha-1,8-dien-3-one and o-menth-1-en-3-one in optically active forms
Starting with (+)-verbenone, readily obtainable from (+)-nopinone, enantioselective preparation of (S)-(+)-4-isopropenyl-, (S)-(−)-4-isopropyl- and (R)-(+)-4-(1-acetoxy-1-methylethyl)-3-methyl-2-cyclohexen-1-ones was accomplished with little loss of stereochemical integrity via BF3-induced cyclobutane-opening of (+)-4-(methylene)nopinone. As we have developed an efficient chemical transformation of