Facile and Environmentally Benign Zn-Mediated Cyclopropanation of Electron-Deficient 2-Iodoethyl-Substituted Olefins via Radical 3-<i>exo</i>-<i>trig</i>Manner
作者:Hideo Togo、Daisuke Sakuma
DOI:10.1055/s-2004-834828
日期:——
An efficient, simple, cheap, and environmentally benign preparation of cyclopropanes via 3-exo-trig manner from various electron-deficient 2-iodoethyl-substituted olefins with zinc powder in a mixture of t-butyl alcohol and water was achieved.
Facile preparation of cyclopropanes from 2-iodoethyl-substituted olefins and 1,3-dihalopropanes with zinc powder
作者:Daisuke Sakuma、Hideo Togo
DOI:10.1016/j.tet.2005.07.103
日期:2005.10
Two efficient, simple, cheap, and environmentally benign preparations of cyclopropanes were achieved. One is the formation via 3-exo-trig manner from various electron-deficient 2-iodoethyl-substituted olefins with zinc powder in a mixture of t-butyl alcohol and water, and the other is the formation via 3-exo-tet manner from various 1,3-dihalopropanes with zinc powder in ethanol.
Synthesis of cyclopropanols via cyclopropanation of zinc enolates
作者:Saeko Ito、Hiroshi Shinokubo、Koichiro Oshima
DOI:10.1016/s0040-4039(98)01036-3
日期:1998.7
with diethylzinc afforded zinc enolates which were converted into the corresponding cyclopropanols in good yields upon treatment with CH2I2 and Et2Zn. The use of α-iodoketone having a carbon-carbon double bond as a substrate proved that cyclopropanation of the enolate moiety proceeded chemoselectively. Cyclopropanation of the zinc enolates derived from α,β-unsaturated ketones via 1,4-addition of organozinc
α-碘酮与二乙基锌的反应提供了烯醇锌,将其用CH 2 I 2和Et 2 Zn处理后可以良好的产率转化成相应的环丙醇。使用具有碳-碳双键的α-碘酮作为底物证明了烯醇盐部分的环丙烷化是化学选择性进行的。还通过有机锌物质的1,4-加成实现了α,β-不饱和酮衍生的烯醇锌的环丙烷化。
DANHEISER, R. L.;SAVOCA, A. C., J. ORG. CHEM., 1985, 50, N 13, 2401-2403