Process for the manufacture of unsaturated ketones of the cyclopentano-polyhydrophenanthrene series

摘要

500,186. Sex hormones. SCHERING KAHLBAUM AKT.-GES. June 1, 1937, No. 15255. Convention date, June 2, 1936. Samples furnished. [Class 2 (iii)] Unsaturated ketones of the cyclopentanopolyhydrophenanthrene series are prepared by treating the corresponding secondary alcohols in the form of their metal alcoholates or in the presence of other metal alcoholates with the exception of a tertiary alcoholate of aluminium or a tertiary alcoholate of magnesium chloride with an excess of an aldehyde or a ketone. In the cases where other metal alcoholates are used, the preferred compounds are magnesium or aluminium alcoholates. The larger the excess of the aldehyde or ketone which is employed the more complete is the oxidation. The process is stated to yield a very pure product, so that simple recrystallization is all that is necessary to give complete purity. Chemical purification methods, such as by means of semicarbazide may, however, also be employed. In examples : (1) a cyclohexanone solution of cholesterol is treated with aluminium isopropylate for four hours at 100 C. and then steam distilled. Interaction with semicarbazide gives the semicarbazone of cholestenone; (2) a xylene solution of cholesterol is treated with aluminium isopropylate to form aluminium cholesterylate. This is then oxidized to cholestenone with cyclohexanone; (3) cholesterol is converted into cholestenone by means of magnesium chlorethylate in a manner similar to the process of example (1); (4) a cyclohexanone solution of pregnenol-(3)-one-(20) is treated with aluminium isopropylate to give the corpus luteum hormone; (5) a oyclohexanone solution of dehydroandrosterone is treated with aluminium isopropylate to give androstendione: (6) a cyclohexanone solution of androstendiol-monobenzoate-(17) is treated with aluminium isopropylate to give testosterone benzoate. Small amounts of starting material are removed by reaction with phthalic anhydride. Samples have been furnished under Sect. 2 (5) of: (1) stigmastadienone prepared by the treatment of stigmasterol in acetone solution with aluminium isopropylate; (2) corpus luteum hormone prepared by the treatment of pregnenol-(3)-one-(20) in xylene solution with an acetone solution of aluminium isopropylate ; (3) testosterone benzoate prepared by the treatment of androstendiol-monobenzoate-(17) in cyclohexanone solution with aluminium isopropylate. Unchanged starting material is removed with phthalic anhydride.