Facile access toN-formyl imide as anN-formylating agent for the direct synthesis ofN-formamides, benzimidazoles and quinazolinones

N-Formamide synthesis usingN-formyl imide with primary and secondary amines with catalytic amounts ofp-toluenesulfonic acid monohydrate (TsOH center dot H2O) is described. This reaction is performed in water without the use of surfactants. Moreover,N-formyl imide is efficiently synthesized using acylamidines with TsOH center dot H2O in water. In addition,N-formyl imide was successfully used as a carbonyl source in the synthesis of benzimidazole and quinazolinone derivatives. Notable features ofN-formylation of amines by usingN-formyl imide include operational simplicity, oxidant- and metal-free conditions, structurally diverse products, and easy applicability to gram-scale operation.