Patent ID: 9029556
Filing Date: 2015-05-12
Classification: C07D

Abstract:
1. A process for preparing 3-(3-chloro-1H-pyrazol-1-yl)pyridine (5b) which comprises a) treating 3-bromopyridine with 3-aminopyrazole in a water-miscible polar aprotic organic solvent at a temperature of about 75° C. to about 155° C. in the presence of a catalytic amount of copper chloride and a base to provide 3-(3-amino-1H-pyrazol-1-yl)pyridine (8a) b) crystallizing the 3-(3-amino-1H-pyrazol-1-yl)pyridine (8a) from water; c) treating the 3-(3-amino-1H-pyrazol-1-yl)pyridine (8a) in aqueous hydrochloric acid with sodium nitrite a temperature of about 0° C. to about 25° C. to provide the diazonium salt (8b) and d) treating the diazonium salt (8b) with copper chloride a temperature of about 0° C. to about 25° C.