Trityl chloride → 2-[4-Hydroxyphenyl]-1-cyclohexyl-5-[2-(trityl)-2h-tetrazol-5-yl]-1h-benzimidazole

Participants

Reaction Conditions

Reaction Steps

Trityl chloride (4.57 g, 0.0164 mol) and N,N-diisopropylethylamine (2.42 g, 0.0187 mol) were added to a stirred mixture of compound 21 (7.4 g, 0.0156 mol) in DMF (36 mL). The mixture was stirred for 18 h at an oil bath temperature of 70° C. The mixture was cooled and poured into a mixture of ethyl acetate and water to precipitate the fully protected benzimidazole, 2-[4-(tert-butyldimethylsilyoxy)phenyl]-1-cyclohexyl-5-[2-(trityl)-2H-tetrazol-5-yl]-1H-benzimidazole. The solid was collected, washed with cold water and dried to afford the protected benzimidazole as a colorless solid (9.1 g, 81% yield). ESI-MS m/e 717 (M+1). HPLC purity (uv) 94%.

Provenance & Evidence