Novel and Efficient Synthesis of Benzimidazole and Benzthiazole Moieties Mediated by Triflic Anhydride and 2‐Nitropyridine

In the present report, inter and intramolecular C−N bond formation between the carbonyl carbon of urea or amide functional group with various amines mediated by triflic anhydride and 2‐nitropyridine is successfully investigated for the first time. The versatility of the method is demonstrated by exploring it on a wide range of substrates to synthesize diversified 2‐aminobenzimidazole, 2‐aminopyridoimidazole and 2‐substituted benzimidazole and benzthiazoles. Short reaction time, high yields and applicability in milder metal free reaction conditions are the highlights of the present methodology. In the present report, inter and intramolecular C−N bond formation between thecarbonyl carbon of urea oramide functional groupwith various amines mediated by triflic anhydride and 2‐nitro pyridine is successfully investigated for the first time. The versatility of the method is demonstrated by exploring it on a wide range of substrates to synthesize diversified 2‐aminobenzimidazole, 2‐aminopyridoimidazole and 2‐substituted benzimidazole and benzthiazoles. Short reaction time, high yieldsand applicability inmilder metalfree reaction conditions are the highlights of the present methodology.