Acid-Promoted Direct C-H Carbamoylation at the C-3 Position of Quinoxalin-2(1)-ones with Isocyanide in Water.

Described herein is a concise and practical direct amidation at the C-3 position of quinoxalin-2(1)-ones through an acid-promoted carbamoylation with isocyanide in water. In this conversion, environmentally friendly water and commercial inexpensive isocyanide were used as a solvent and carbamoylation reagent, respectively. This study not only provides a green and efficient strategy for the construction of 3-carbamoylquinoxalin-2(1)-one derivatives that can be applied to the synthesis of druglike structures but also expands the application of isocyanide in organic chemistry.