Intramolecular cyclizations of α-stannyl radicals to acylsilanes: regiospecific syntheses of five-membered cyclic silyl enol ethers
作者:Yeun-Min Tsai、Sheng-Yueh Chang
DOI:10.1039/c39950000981
日期:——
α-Stannyl radicals generated from acylsilanes 5, 13 and 14 cyclize to give good yields of cyclic silyl enol ethers after sequential cyclizations, radical Brook rearrangements and β-scissions.
A mild protocol for hydroacylation of enones through photosensitization of acyl silanes with thioxanthone under blue light (455 nm) irradiation is reported. A Brønsted acid is used as a cocatalyst in the reaction. The versatility of the method is demonstrated through inter- and intramolecular hydroacylation reaction. The hydroacylation product is applied for synthesizing an anti-HCV agent. Mechanistic