A useful methodology for the synthesis of 2-methyl-4-nitrobenzimidazoles

Article abstract of DOI:10.1055/s-1992-26359

Cyclocondensation of 3-nitro-1,2-benzenediamines 2 with 2,4-pentanedione provides a convenient route for the preparation of 2-methyl-4-nitrobenzimidazoles 3. A discrepancy in the literature regarding the 5-chloro-, 5-methoxy- and 5-methyl derivatives of the title compounds is discussed.