Heterocyclic steroids—Part VIII: Studies on the total synthesis of racemic 2-phenyl-7-methyl-3-oxa-A-nor-14β-estra-1,5 (10),6,8-tetraen-17α-ol

2-Phenyl-6-methyl-4-oxo-4,5,6,7-tetrahydrobenz ofuran (II) is converted into racemic 2-phenyl-7-methyl-3-oxa-A-nor-14β-estra-1,5(10),6,8-tetraen-17α-ol (VIII). Recent publications on A-ring heteroaromatic steroids and the total synthesis of heterocyclic steroids (l to 5) indicated that there has been no report on the total synthesis of A-nor-2-phenyl-5-oxaequilenin. It is also relevant to state here that steroids methylated in the 6β (6,7) and 7α (8) positions have been known to furnish biologically interesting products. Encouraged by these findings, we wish to report here the total synthesis of the title compound (VIII) (9). The required bicyclic ketone (II) was prepared in two steps starting with 5-methylcyclohexane-1,3-dione (10). 5-Methylcyclohexane-l,5-dione on treatment with phenacyl bromide in the presence of anhydrous potassium carbonate and dry chloroform at. room temperature afforded 2-phenacyl-5-methylcyclohexane-1,3-dione (I). Cyclodehydration of (I) with concentrated sulphuric acid at 0°