N -Formamide as a carbonyl precursor in the catalytic synthesis of Passerini adducts under aqua and mechanochemical conditions.

A new simple, efficient, and environmentally friendly protocol is presented for the catalytic synthesis of α-acyloxycarboxamides using N -formamides as a carbonyl precursor under aqua and mechanochemical conditions. Immobilized sulfuric acid on silica gel was employed for the synthesis of desired products, via the reaction of benzoic acid, 1-napthylisocyanide and various heterocyclic N -formamides. After a careful optimization of the reaction conditions, the desired Passerini products were obtained in high to excellent yields in short reaction times (10-30 min) at room temperature. The highly efficient and environmentally friendly method provides a facile access to a library of α-acyloxycarboxamides derivatives for future research on bioactivity screening.