Photo-induced electron transfer (PET) of silyl enol ethers has been used
to achieve several fused ring systems. However, the method has limited
utility due to its narrow substrate scope, low product yields,
unsatisfactory stereo- and regio- selectivity. Herein, we report a
PET-triggered cascade reaction of silyl enolate to angular fused
tricyclic scaffold. The reaction demonstrates good substrate scope and
stereo-selectivity. The regio- and stereo- selectivity of this cascade
reaction is elucidated via DFT calculation and conformational
analysis.
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