Intramolecular radical cyclization approach to access highly substituted indolines and 2,3-dihydrobenzofurans under visible-light.

The combination of visible-light and tris(trimethylsilyl)silane promoting intramolecular reductive cyclization protocol for the synthesis of functionalized indolines and 2,3-dihydrobenzofurans has been developed. The transformations occur in the absence of transition metal and additional photocatalyst. In addition, quantum yield (Φ) was determined and electron paramagnetic resonance spectroscopy was performed to better understand the reaction pathway.