Photocatalytic Synthesis of Diarylmethyl Silanes via 1,6-Conjugate Addition of Silyl Radicals to p -Quinone Methides.

A novel photocatalytic method for the preparation of diarylmethyl silanes was reported through silyl radicals addition strategy to p -QMs ( p -quinone methides). This protocol could tolerate a variety of functional groups affording the corresponding silylation products with moderate to excellent yields. The resulting silylation products could be easily converted into a series of bioactive GPR40 agonists and useful p -QMs precursors for the synthesis of compounds possessing both quaternary carbon centers and silicon substituents through simple operation. A plausible mechanism of silyl radicals to p -QMs was proposed on the basis of experimental results and previous literature.