Preparation of tetrahydrofuran, γ-lactone, chromanol and pyrrolidine systems by sequential 5-exo-digonal radical cyclization, 1,5-hydrogen transfer from silicon, and 5-endo-trigonal cyclization
作者:Derrick L. J. Clive、Wen Yang
DOI:10.1039/cc9960001605
日期:——
Sequential 5-exo-digonal radical closure, intramolecular 1,5-hydrogen transfer from silicon to carbon, and 5-endo-trigonal closure of the resulting silicon-centred radicals are used to make five- and six-membered heterocycles containing oxygen or nitrogen.
Preparation of Polycyclic Systems by Sequential 5-<i>E</i><i>xo</i>-<i>D</i><i>igonal</i> Radical Cyclization, 1,5-Hydrogen Transfer from Silicon, and 5-<i>E</i><i>ndo</i>-<i>T</i><i>rigonal</i> Cyclization
作者:Derrick L. J. Clive、Wen Yang、Aaron C. MacDonald、Zhongren Wang、Michel Cantin
DOI:10.1021/jo001124x
日期:2001.3.1
diagonal cyclization, and the resulting vinyl radical abstracts hydrogen from silicon to afford a silicon-centered radical. This radical closes in a 5-endo trigonal manner to generate radicals of type 4, which are reduced (4 --> 5) by stannane, except when the starting acetylene carries a terminal trimethylstannyl group. In this case, radicals 4 expel trimethylstannyl radical to afford vinyl silanes