Abstract: The present invention provides a continuous process for the production of 1,2,2,2-tetrafluoroethyl difluoromethyl ether (desflurane) which comprises feeding continuously optimum molar quantities of 1-chloro-2,2,2-trifluoroethyl difluoromethyl ether (CF3CHClOCHF2, Isoflurane) and anhydrous hydrogen fluoride, in a reactor in the vapor phase over a fluorination catalyst system comprising a metal pentahalide absorbed on a supporting substrate at a temperature ranging from 100° C. to 180° C., and separating 1,2,2,2-tetrafluoroethyl difluoromethyl ether (desflurane) continuously from the reactor. The process of the present invention enables continuous removal of desflurane product thereby minimizing co-production of byproducts and resulting in high conversion efficiency and yield of desflurane.

Abstract: The present invention provides a continuous process for the production of 1,2,2,2-tetrafluoroethyl difluoromethyl ether (desflurane) which comprises feeding continuously optimum molar quantities of 1-chloro-2,2,2-trifluoroethyl difluoromethyl ether (CF3CHClOCHF2, Isoflurane) and anhydrous hydrogen fluoride, in a reactor in the vapour phase over a fluorination catalyst system comprising a metal pentahalide absorbed on a supporting substrate at a temperature ranging from 100° C. to 180° C., and separating 1,2,2,2-tetrafluoroethyl difluoromethyl ether (desflurane) continuously from the reactor. The process of the present invention enables continuous removal of desflurane product thereby minimizing co-production of byproducts and resulting in high conversion efficiency and yield of desflurane.

Abstract: A process for the preparation of N-[3-[3-(dimethylamino)-1-oxo-2-propenyl]phenyl]-N-ethyl acetamide of formula II, comprising reacting a compound N-[3-[3-(dimethylamino)-1-oxo-2-propenyl]phenyl]acetamide of formula III, with an ethylating agent in the presence of a strong alkali metal hydroxide and a phase transfer catalyst in a polar-aprotic solvent, and a process for preparation of Zaleplon, which is substantially free of impurities using the said compound of formula II.

Abstract: Improved processes using primary, secondary and tertiary alcohols and with safer mode of introduction of the reagent and reaction conditions are described. Further, the process of manufacture of Losartan potassium by use of alkali metal salt such as Potassium carbonate is disclosed. A process for preparation of the polymorphic Form I of Losartan potassium is also disclosed herein.