Potassium Hydroxide → 3beta-Hydroxy-5alpha-pregn-16-ene-11,20-dione

Participants

Reaction Steps

A solution of 3β-acetoxy-5α-pregn-16-ene-11,20-dione (Chamberlin et al., J. Amer. Chem. Soc., 1951, 73, 2396) (25.7 g.) in dioxan (500 ml.) was treated with potassium hydroxide (10 g.) and water 250 ml. and the mixture allowed to stand at room temperature for 1 hour. After a further 1 hour at 40° the mixture was diluted with water and the product filtered off. The crude material was dissolved in chloroform and filtered through a column of grade III neutral alumina (ca. 100 g.). The material obtained was crystallised from acetone petroleum to give pure title compound (17.65 g.), as small plates, m.p. 217.5°, [α]D +82.9° (c 1.1), λmax. 234 nm. (ε 10,100).

Provenance & Evidence