m-Chloroperbenzoic acid → 6alpha,7alpha-Diepoxypregn-4-en-3one

Participants

Reaction Steps

To a solution of 0.43 g (1.0 mmole) of 20-(5,5-dimethyl-1,3-dioxan-2-yl)-1α,2α-epoxypregna-4,6-dien-3-one in 10 ml of methylene chloride was added 3 ml of 0.5M-aqueous sodium hydrogen carbonate solution under stirring and cooling in an ice-water bath, followed by gradual addition of 0.34 g (2.0 mmoles) of m-chloroperbenzoic acid. The mixture was stirred at room temperature for 2 days. The reaction mixture thus obtained was subjected to phase separation and the aqueous layer was extracted twice with 10 ml portions of methylene chloride. The extract was combined with the organic layer obtained above and the mixture was washed successively with aqueous potassium iodide solution and aqueous sodium chloride solution, and dried over magnesium sulfate. The solvent was then distilled off under reduced pressure and the residue was purified by silica gel chromatography (eluent: ethyl acetate-hexane=1:10, v/v) to recover 0.35 g of 20-(5,5-dimethyl-1,3-dioxan-2-yl)-1α,2α;6α,7α-diepoxypregn-4-en-3-one (yield: 79%). The 1H-MNR and IR spectra of this product were in agreement with those of the 20-(5,5-dimethyl-1,3-dioxan-2-yl)-1α,2α;6α,7α-diepoxypregn-4-en-3-one obtained in Example 7.

Provenance & Evidence