Tris(trimethylsilyl)silane and visible-light irradiation: a new metal- and additive-free photochemical process for the synthesis of indoles and oxindoles

A combined tris(trimethylsilyl)silane and visible-light-promoted intramolecular reductive cyclization protocol for the synthesis of indoles and oxindoles has been developed. This straightforward and efficient method shows tolerance towards a broad spectrum of functional-groups and enables rapid and practical synthesis of functionalized nitrogen-based heterocycles in high yields under additive and metal-free, mild photochemical conditions.