Synthesis of N‐Aryl‐2‐substituted Tetrahydrobenzimidazoles via Direct N‐Arylation

Abstract

A series of novel N‐aryl‐2‐substituted tetrahydrobenzimidazoles has been synthesized via direct N‐arylation of 2‐substituted tetrahydrobenzimidazoles, which was accomplished by a medium aryl electrophile, 4‐methylsulfonylfluorobenze, in the presence of 37% KF/Al₂O₃ and 18‐crown‐6 in fair yields under mild reaction conditions. Meanwhile, the hydrogenation of 2‐phenylbenzimidazole was studied.

Keywords:

• N‐arylation
• hydrogenation
• selective cyclooxygenase‐2 inhibitors
• tetrahydrobenzimidazole