摘要 |
An optically active 4-(4-substituted-2,6-dihydroxyphenyl)-6,6-dimethyl-2-norpinanone is reacted with a protonic acid to provide an optical isomer of a cis-1-hydroxy-3-substituted-6,6-dimethyl-6,6a,7,8,10,10a-hexahydro-9H- dibenzo[b,d]pyran-9-one. Reaction of said norpinanone with a Lewis acid provides an optical isomer of trans-1-hydroxy-3-substituted-6,6-dimethyl-6,6a,7,8,10,10a-hexahydro-9 H-dibenzo[b,d]pyran-9-one. The optically active norpinanones are prepared by reaction of a 5-substituted-resorcinol with an optically active 6,6-dimethyl-2,4-diacetoxy-2-norpinene or an optically active 6,6-dimethyl-2,2-diacetoxy-3-norpinene, which compounds are derived from optically active beta -pinenes. |