Acetic Anhydride → HCID 56618400, compound

Participants

Reaction Conditions

Reaction Steps

0.24 ml of acetanhydride, 0.36 ml of triethylamine and 50 mg of 4-dimethylaminopyridine are added to 400 mg of the pregna-1,4,17(20)-triene-21-ol-3-one produced in accordance with Example 1 in 10 ml of absolute methylene chloride, followed by stirring for 30 minutes at 0° C. A thin-layer chromatogram shows that the reaction is quantitative after this period. The reaction solution is successively washed with ice-cold dilute HCl, NaHCO3 solution and finally with water. The CH2Cl2 phase is dried over Na2SO4, the drying agent is filtered off and the residue is concentrated to dryness. The residue is substantially pure product in a yield of more than 90%. 1H-NMR (80 MHz, COCl3 ; δ-value):

Provenance & Evidence