PROCESS FOR THE PREPARATION OF (1R, 2S, 4R) -(-) -2 - (2 -DIMETHYLAMINOETHOXY) -2 -PHENYL -1,7,7 - TRIMETHYLBICYCLO 2.2.1 HEPTANE

摘要

The invention relates to a process for the preparation of (1R,2S,4R) -(-) -2- (2-dimethylaminoethoxy) -2 -phenyl -1,7,7- trimethylbicyclo [2.2.1] heptane of Formula (I) and pharmaceutically acceptable acid addition salts thereof starting from (1R,2S,4R) -(-) -2- phenyl -1,7,7 - trimethylbicyclo [2.2.1] heptane -2-ol of Formula (III) and optionally converting (1R,2S,4R)-(-)-2- (2-dimethylaminoethoxy) -2-phenyl-1,7,7- Mtrimethylbicyclo [2.2.1] heptane into a salt thereof, which comprises reacting an alkali salt of (1R,2S,4R)-(-) -2-phenyl-1,7,7- trimethylbicyclo [2.2.1] heptane-2-ol of Formula (III) with a 2-halo-N,N- dimethyl-acetamide of general Formula (IV) (wherein X stands for halogen) and reducing the (1R,2S,4R)-(-)-N, N-dimethyl- (2-phenyl-1,7, 7-trimethylbicyclo [2.2.1] hept-2-yl) -oxy-acetamide of Formula (V) thus obtained. The compound of Formula (I) is a known anxiolytic pharmaceutical active ingredient. The process of the invention is readily feasible on industrial scale too, can be carried out through a crystalline new last intermediate which can be easily purified and provided a highly pure end product with excellent yields.