Lewis Acid-Mediated Isothiocyanation and Chlorination of Quinoxalin-2(1)-ones under Visible Light Conditions.

Lewis acid-mediated selective C3-isothiocyanation of quinoxalin-2(1)-ones using -thiocyanatosaccharin as an isothiocyanate source under visible light conditions at room temperature is described. Under similar conditions with -chlorosaccharin, the C3-chlorination of quinoxalin-2(1)-ones achieved a 2 h time frame. Good to an excellent yield of products was obtained in both cases with broad functional group tolerance.

Correction: Pd-catalyzed annulation of imidazo[1,2-]pyridines with coumarins and indoles: synthesis of benzofuran and indole fused heterocycles.

Correction for 'Pd-catalyzed annulation of imidazo[1,2-]pyridines with coumarins and indoles: synthesis of benzofuran and indole fused heterocycles' by Rashmi Semwal , , 2022, , 1585-1588, DOI: 10.1039/D1CC06803B.

Pd-catalyzed annulation of imidazo[1,2-]pyridines with coumarins and indoles: synthesis of benzofuran and indole fused heterocycles.

Palladium-catalyzed annulation of imidazo[1,2-]pyridines with coumarins provided benzofuran fused transannulated products in good to excellent yields a decarbonylative approach, while imidazo[1,2-]pyridines with -methyl indoles in the presence of palladium and base yielded conjugated imidazopyridine fused indole derivatives. Additional experiments revealed that the presence of the phenyl ring at the C-2 position of imidazo[1,2-]pyridines is essential for the annulation than the alkyl groups. Both transformations follow the ionic mechanism by Pd-catalyzed double C-H bond activation.