An iodine-mediated oxidative [4+1] cyclization of enamines with TMSN for the synthesis of 2,5-disubstituted imidazole-4-carboxylic derivatives has been developed. The mechanistic studies revealed that the reaction proceeds through a sequential removal of two nitrogen atoms from TMSN. The synthetic utility was further demonstrated with a gram-scale reaction and various derivatization transformations of the products.
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