Intramolecular addition of aryl radicals to vinylogous urethanes: studies toward preparation of the oxindole portion of gelsemine
作者:David J. Hart、Shung C. Wu
DOI:10.1016/s0040-4039(00)79873-x
日期:1991.8
Free radical cyclization of vinylogous urethanes 5 and 12 gave spiro oxindoles 6 and 13 + 14, in 95% and 84% yields, respectively. Cyclization of projected gelsemine intermediate 19 resulted in the formation of oxindole 22 via a cyclization, 1,4-hydrogen atom transfer, reduction sequence.
含乙烯基的氨基甲酸酯5和12的自由基环化反应分别产生了95%和84%的螺氧基吲哚6和13 + 14。投射的半胱氨酸中间体19的环化通过环化,1,4-氢原子转移,还原序列而形成羟吲哚22。