remove impurities and the product obtained by evaporating the methylene chloride to obtain the free base of compounds of formula ib and if desired converting to an acid addition salt in a suitable solvent and recrystallizing from a suitable solvent mixture the method is illustrated in example 6 method c is represented by the following equation str15 wherein ar 1 ar 2 y x p r r 1 r 2 and r 3 are selected from values assigned under formula i with the proviso that when r 1 is not hydrogen r 2 and r 3 must be other than hydrogen or r 1 is the same as r 2 and r 3 is hydrogen generally in method c the 1 unsubstituted heterocyclic compound is reacted with phosgene or thiophosgene in a suitable organic solvent plus proton sponge u00ae which is 1 8 bis dimethylamino naphthylene followed by extraction washing with dilute sulfuric acid and the organic layer is dried and evaporated to an oil the oil is dissolved in tetrahydrofuran and reacted with an amine of formula v the reaction mixture is stripped to dryness and the residue is partitioned between water and a suitable organic solvent evaporation of the solvent yields the crude free base ib as can be seen in the foregoing process description and following examples.