Benzene → HCID 12851169, compound

Participants

Reaction Steps

To a solution of 2.7 g of (20S)-21-acetyloxy-20-methylpregn-5-ene-1α,3β-diol in 120 ml of benzene containing 30 mg of anhydrous p-toluenesulfonic acid was added 4.2 ml of 3,4-dihydro-2H-pyran. The reaction mixture was left at 20° for 2 hr. and then poured onto an ice-cold 5% sodium bicarbonate solution. The product was extracted with ether. The ether extract was washed with saturated sodium chloride solution, dried (Na2SO4) and evaporated under reduced pressure. After drying at 0.05 mm, 4.3 g of (20S)-21-acetoxy-1α,3β-bis[(tetrahydro-2H-pyran-2-yl)oxy]-20-methylpregn-5-ene was obtained which, after recrystallization from methanol--ether, had mp 155°-161°.

Provenance & Evidence