An improved process for the preparation of R(+)1,2,3,6-tetrahydro-4-phenyl-1-[(3-phenyl-3-cyclohexen-1-yl)methyl]pyridine by a novel synthesis is described where 5-oxo-3-phenyl-3-cyclohexene-carboxylic acid is converted in five operations to the desired product, as well as processes for the resolution of 5-oxo-3-phenyl-3-cyclohexenecarboxylic acid using cinchonidine to afford (S)5-oxo-3-phenyl-3-cyclohexenecarboylic acid or alpha -chymotrypsin to selectively hydrolyze n-butyl 5-oxo-3-phenyl-3-cycohexenecarboxylate to afford (S)5-oxo-3-phenyl-3-cyclohexenecarboxylic acid as well as other valuable intermediates used in the processes.
展开▼