Hetero-cyclic compounds are widely found in natural products, pharmaceuticals and materials, thus drawing the considerable attention from the synthetic community. Commonly, alkaline earth metals are earth abundant and environmentally friendly...

A photo-triggered cascade cyclization of silyl enolate to prepare angularly fused tricyclic scaffold is developed. The reaction demonstrates good substrate scope and stereo-selectivity. The excellent stereo- and regio-selectivity for this cascade reaction is elucidated via conformational analysis and DFT calculation, respectively.

Comprehensive SummaryPhoto‐induced electron transfer (PET) of silyl enol ethers has been employed to synthesize several fused ring systems. However, the method has limited applicability due to its narrow substrate scope, low product yields, unsatisfactory stereo‐ and regioselectivity. Herein, we report a PET‐triggered cascade reaction of silyl enolates that leads to the formation of angularly fused tricyclic scaffolds. The reaction exhibits broad substrate scope and excellent stereoselectivity. The regio‐ and stereoselectivity of this cascade reaction is elucidated via DFT calculation and conformational analysis.