| 摘要 |
Reaction of cis-1-hydroxy-3-substituted-6,6-dimethyl-6,6a,7,8,10,10a-hexahydro-9H- dibenzo[b,d]pyran-9-ones with an aluminum halide in an unreactive organic solvent effects complete epimerization to provide the corresponding trans-1-hydroxy-3-substituted-6,6-dimethyl-6,6a,7,8,10,10a-hexahydro-9 H-dibenzo[b,d]pyran-9-one. |
