Environmentally friendly TPDS-mediated free radical ring expansion of α-haloalkyl cyclic β-keto esters
作者:Masaaki Sugi、Hideo Togo
DOI:10.1016/s0040-4020(02)00241-7
日期:2002.4
Reactivities of tetraphenyldisilane (TPDS), tris(trimethylsilyl)silane, and tributyltin hydride in the radicalringexpansion of α-haloalkyl cyclic β-keto esters were examined. Among these reagents, TPDS was found most effective for the preparation of medium-sized cyclic compounds in terms of yields and ring-expansion/reduction selectivity.
Zinc- and Indium-Mediated Ring-Expansion Reaction of α-Halomethyl Cyclic β-Keto Esters in Aqueous Alcohol
作者:Masaaki Sugi、Daisuke Sakuma、Hideo Togo
DOI:10.1021/jo030092l
日期:2003.10.1
Radical ring-expansion reaction of various alpha-halomethyl cyclic beta-keto esters and alpha-halomethyl benzocyclic beta-keto esters and chain-extension reaction of alpha-halomethyl beta-keto esters with zinc powder and indium powder in refluxing aqueous alcohol were carried out to generate the corresponding ring-expansion and chain-extension products. As the results indicate, it was found zinc powder