Benzene → HCID 13044103, compound

Participants

Reaction Steps

1.8 ml. of 3,4-dihydro-2H-pyran and 20 mg of anhydrous p-toluenesulphonic acid were added to a solution of 2.45 g of (20S)-1α,2α-epoxy-21-hydroxy-20-methyl-pregna-4,6-dien-3-one in 125 ml. of absolute benzene. After standing at room temperature for 1 hour, the solution was diluted with ether, washed with saturated sodium bicarbonate solution and water, dried over sodium sulphate and concentrated in a water-jet vacuum. The residue was chromatographed on 30 g of silica gel using hexane/ether (4:1) for the elution, there being obtained 2.0 g (65%) of (20S)-1α,2α-epoxy-20-methyl-21-tetrahydropyranyloxy-pregna-4,6-dien-3-one. After recrystallisation from hexane, the product melted at 101°-102° C. and was shown by thin-layer chromatography, mixed melting point and IR spectrum to be identical with the compound prepared as described in Example 7.

Provenance & Evidence