Patent ID: 6407255
Filing Date: 2002-06-18
Classification: A61P,C07D

Abstract:
A process for the preparation of 3-chloromethyl-1,2,4-triazolin-5-one which comprises:(i) treatment of semicarbazide hydrochloride with benzyloxyacetyl chloride under Schotten-Baumann conditions to give benzyloxyacetylsemicarbazide; (ii) cyclisation of the product of step (i) under basic conditions to give 3-benzyloxymethyl-1,2,4-triazolin-5-one; (iii) hydrogenation of the product of step (ii) to give 3-hydroxymethyl-1,2,4-triazolin-5-one; and (iv) treatment of the product of step (iii) with a chlorinating agent to give 3-chloromethyl-1,2,4-triazolin-5-one.