PROCESS FOR PREPARATION OF SUBSTANTIALLY OPTICALLY PURE (R)- AND (S)- ENANTIOMERS OF KETAMINE AND ITS PHARMACEUTICAL ACCEPATABLE SALTS

A new synthesis for the preparation of optically pure (R)-2-(2-chlorophenyl)-2-(methylamino)cyclohexanone [(R)-Ketamine] as well as (S)-2-(2-chlorophenyl)-2-(methylamino)cyclohexanone [(S)-Ketamine] and its pharmaceutically acceptable salts by effectively resolving R,S-Ketamine base with Di-p-toluoyl-L-tartaric acid (DPTTA) in alcoholic solvents to separate Di-p-toluoyl-L-tartaric acid, salt of R-Ketamine and Di-p-toluoyl-L-tartaric acid salt of S-Ketamine respectively. The Di-p-toluoyl-L-tartaric acid salts of R-Ketanine and   S-Ketamine are separated by crystallization process as a particular salt is soluble or less soluble in a particular alcoholic solvent system. The salt is ruptured by an alkali to get Optically Pure (R) and (S)-Ketamine Base which are treated with hydrochloric acid to get R-Ketamine hydrochloride and S-Ketamine hydrochloride without any need of purification.