Patent ID: 6162922
Filing Date: 2000-12-19
Classification: C07D

Abstract:
A process for the preparation of a compound of formula I or its salt ##STR10## wherein R is lower alkyl of 1-4 carbon atoms or lower alkoxy of 1-3 carbon atoms, comprising the steps of:reacting a 2-R-1-3-diazaspiro[4.4]nonan-4-one hydrochloride of formula II ##STR11## wherein R has the meaning given above, with a 4'(halomethyl)[1,1'-biphenyl]-2-carbonitrile of formula III ##STR12## wherein Hal is chlorine, bromine or iodine, in a water-immiscible organic solvent, in the presence of an inorganic base and a phase transfer catalyst selected from quaternary onium salts, cyclic polyethers, open chain polyethers, N-alkylphosphoramides and methylene-bridged phosphorous and sulfur oxides, separating the organic solvent, optionally drying the organic solvent, filtering the organic solvent, evaporating the filtered organic solvent to give the compound of the formula I, crystallizing the compound of the formula I from an organic solvent and optionally converting the compound of formula I into its salt.