Ammonium Chloride → 3alpha-Hydroxy-16alpha-methyl-5alpha-pregnane-11,20-dione

To a stirred slurry of cuprous iodide (950 mg) in dry ether (75 ml) under dry nitrogen at 0° was added a solution of methyl-lithium in ether (1.6M; 6 ml.) until the initially formed yellow precipitate just rediseolved to give a clear solution. To the stirred solution at 0° was added a solution of 3α-hydroxy-5α-pregn-16-ene-11,20-dione (600 mg) in dry tetrahydrofuran (50 ml.). During the addition a bright yellow precipitate formed. The mixture was stirred at 0° for 30 minutes, and then poured into cold, saturated ammonium chloride solution (200 ml.) More ether (200 ml) was added and the organic layer was separated, washed with saturated ammonium chloride solution (200 ml) and with water (200 ml.) dried over sodium sulphate and purified by preparative t.l.c. in ethyl acetate to give a product which was further purified by preparative t.l.c. in ethyl acetate/chloroform, 1/1 to give a white solid (380 mg) which was recrystallised from ether/petrol to give title compound (248 mg) as colourless plates, m.p. 138°-140°, [α]D + 99°, (c 0.95).

1. customto give a clear solution
2. additionDuring the addition a bright yellow precipitate
3. customformed
4. additionwas added
5. customthe organic layer was separated
6. washwashed with saturated ammonium chloride solution (200 ml) and with water (200 ml.)
7. dry with materialdried over sodium sulphate
8. custompurified by preparative t.l.c
9. customin ethyl acetate to give a product which
10. customwas further purified by preparative t.l.c

ORD record

ord-756df4d58f1a472295fa94e4f934848c

Source dataset

uspto-grants-1976_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US03943124