Zinc-Catalyzed Alkene Cyclopropanation through Zinc Vinyl Carbenoids Generated from Cyclopropenes
作者:María J. González、Javier González、Luís A. López、Rubén Vicente
DOI:10.1002/anie.201505954
日期:2015.10.5
zinc‐catalyzed reaction of cyclopropenes with alkenes leading to vinylcyclopropane derivatives is reported. A broad range of alkenes (including highly substituted or functionalized alkenes) is compatible with this protocol. On the basis of trapping experiments and computational studies, this cyclopropanation reaction is proposed to proceed through initial formation of an electrophilic zinc vinyl carbenoid intermediate
atom-efficient route for the synthesis of a wide range of enantioenriched alkynylcyclopropane derivatives in high yields (65–96%) and excellent stereoselectivity (>20:1 dr; 90–99% ee). Elaboration of some of the alkynylcyclopropane products through selective transformation of the C≡C moiety has also been demonstrated to give further diversified chiral cyclopropane derivatives which are otherwise difficult
Zinc-Catalyzed Synthesis of Allylsilanes by Si−H Bond Insertion of Vinyl Carbenoids Generated from Cyclopropenes
作者:Sergio Mata、Luis A. López、Rubén Vicente
DOI:10.1002/anie.201703319
日期:2017.6.26
zinc‐catalyzed reaction of cyclopropenes and hydrosilanes provides a convenient route to these versatile unsaturated organosilanes. In this transformation, ZnBr2 serves as an efficient catalyst, allowing the generation of a zinc vinyl carbenoid intermediate, which is subsequently involved in a Si−H bond insertion. The process shows broad scope, and is amenable to substituted and functionalized cyclopropenes
Synthesis of 1,2-divinylcyclopropanes by metal-catalyzed cyclopropanation of 1,3-dienes with cyclopropenes as vinyl carbene precursors
作者:Jesús González、Alba de la Fuente、María J González、Laura Díez de Tejada、Luis A López、Rubén Vicente
DOI:10.3762/bjoc.15.25
日期:——
by the reaction of cyclopropenes with 1,3-dienes is reported. The process relies on the ability of ZnCl2 or [Rh2(OAc)4] to generate metal–vinyl carbene intermediates from cyclopropenes, which effect cyclopropanation of 1,3-dienes. Most of the reactions proceeded in reasonable yields while the diastereoselectivity strongly depends on the structure of the diene. An example of an intramolecular process