Patent ID: 8048904

Claim:
A process for the preparation of Olmesartan medoxomil which comprises i) alkylating ethyl 4-(1-hydroxy-1-methylethyl)-2-propylimidazole-5-carboxylate with 4-[2-(trityltetrazol-5-yl)phenyl]benzyl bromide in the presence of a catalyst and a base in an organic solvent to obtain ethyl 4-(1-hydroxy-1-methylethyl)-2-propyl-1-{4-[2-(trityl tetrazol-5-yl)phenyl]phenyl}methylimidazole-5-carboxylate, ii) hydrolyzing the ethyl 4-(1-hydroxy-1-methylethyl)-2-propyl-1-{4-[2-(trityl tetrazol-5-yl)phenyl]phenyl}methyl imidazole-5-carboxylate to obtain trityl Olmesartan dihydrate, iii) esterifying the trityl Olmesartan dihydrate with 4-chloromethyl-5-methyl-2-oxo-1,3-dioxolene in an organic solvent in the presence of a base and a catalyst to obtain trityl Olmesartan medoxomil, and iv) deprotecting the trityl Olmesartan medoxomil to obtain Olmesartan medoxomil.