Visible light catalyzed Mannich reaction between tert-amines and silyl diazoenolates.

The present work documents the α-C-H functionalization of tertiary amines via the visible light catalyzed Mannich reaction with silyl diazoenolates. The reaction takes place at room temperature with an organic dye, Rose Bengal, as a photocatalyst and oxygen as the oxidant. The resulting multifunctional products bearing an α-diazo-ß-keto group undergo Rh-carbenoid mediated cyclization, affording stable ammonium ylides in high yields.