a method for dehalogenating a compound of the generalized structure ## str1 ## is disclosed where : r 1 , r 2 and r 3 independently are hydrogen or methyl or r 1 and r 3 taken together represent methylene , with the proviso that r 1 , r 2 and r 3 are not all methyl ; x is a halogen ; m is zero , 1 or 2 ; and y is a pharmaceutically acceptable acid . the method comprises contacting compound i with a catalytic hydrogenolysis system to replace the halogen with a hydrogen . a particularly preferred hydrogenolysis system comprises pd / c and ammonium formate . a preferred starting material is ## str2 ##