Steroid analogues. Part 3. Preparation of 4-cyclohexylidenecyclohex-2-enones and 6,7-dinor-5,8-secoestra-4,9-dien-3-ones by Birch reduction of 1-p-methoxyphenylcycloalkanols

Abstract

Reduction of 4-substituted 1-(p-methoxyphenyl)cyclohexanols (8)–(13) with lithium and ethanol in liquid ammonia, followed by hydrolysis, gave 4-(4-substituted cyclohexylidene)cyclohex-2-enones (14)–(22) as the major products; in some cases the corresponding 4-(4-substituted cyclohexyl)cyclohex-3-enones (36) were isolated.

Similar treatment of 3ξ-(p-methoxyphenyl)-6β-methyl-trans-bicyclo[4.3.0]nonane-3ξ, 7β-diol (47) afforded 17β-hydroxy-6,7-dinor-5,8-secoestra-4,9-dien-3-one (42) in moderate yield as a mixture of Δ^1,9 and Δ^4,9-isomers.

4-Cyclohexylidenecyclohex-2-enol (57) was reduced with di-imide to give 4-cyclohexylidenecyclohexanol (58) as the major product.