An improved process for preparation of levonorgestrel

摘要

The present invention provides an improved process for preparation of levonorgestrel (3) which comprises of hydrolysis of 13β-ethyl-3-methoxy-17α-ethynyl-gona-2,5(10)-dien-17β- o1 (2) with an acid in aprotic solvent. The present invention also provides a novel process for purification of crude levonorgestrel (3) by recrystallization from N,N-dimethyl formamide- water; methanol-water mixture.