A Novel 1,3-Stannyl Shift Promoted Intramolecular Cyclizations of α-Stannyl Radicals with a Formyl Group
作者:Sheng-Yueh Chang、Yar-Fang Shao、Shu-Fang Chu、Gang-Ting Fan、Yeun-Min Tsai
DOI:10.1021/ol990199o
日期:1999.9.1
[GRAPHICS]Reactions of alpha-stannyl bromides and xanthates with tributyltin hydride generate a stannyl radicals, Intramolecular cyclizations of these radicals with a formyl group afford gamma-stannyl alkoxy radicals that undergo a 1,3-stannyl shift from carbon to oxygen. The carbon radicals obtained can be trapped inter- or intramolecularly. Approximately, the rates of 5-exo cyclizations of alpha-stannyl radicals with a formyl group and terminal olefin are similar.