Generation and Application of (Diborylmethyl)zinc(II) Species: Access to Enantioenriched <i>gem</i>
-Diborylalkanes by an Asymmetric Allylic Substitution
作者:Yeosan Lee、Jinyoung Park、Seung Hwan Cho
DOI:10.1002/anie.201805476
日期:2018.9.24
We report the successful generation of (diborylmethyl)zinc(II) species by transmetallation beteween isolable (diborylmethyl)lithium and zinc(II) halide (X=Br, Cl) and their application in the synthesis of enantioenriched gem‐diborylalkanes bearing a stereogenic center at the β‐position of the diboryl groups by an asymmetric allylic substitution reaction. The reaction has a broad substrate scope, and
carbonates was reported. This reaction, in the presence of chiral CuOAc/SOP and achiral Pd(dppf)Cl2 catalysts, occurs smoothly with high enantioselectivities (up to 97% ee) . The allylboration products, which contain alkene (or diene) unite and alkylboron group, are easily functionalized. The utility of this protocol was demonstrated through the synthesis of an antipsychotic drug, (-)-preclamol.
The Fe-Catalysed Phosphono-Allylation of Activated Olefins
作者:Susanne Rommel、André P. Dieskau、Bernd Plietker
DOI:10.1002/ejoc.201201563
日期:2013.3
under thermal conditions. The preparation of more densely functionalized phosphonates is still a synthetic challenge. In this paper, we present a convenient one-pot three-component phosphono-allylation of activatedolefins to give phosphonates bearing a variety of functional groups.
A simple diamine as ligand in iron-catalyzed regioselective allylic alkylation
作者:Chenguang Yu、Aihua Zhou、Jing He
DOI:10.1039/c2ra21646a
日期:——
A simple and efficient diamine was found to be an efficient ligand for the iron-catalyzedregioselectiveallylicalkylation between various allyl carbonates and nucleophiles, affording excellent yields and good regioselectivity (up to 94% and >20 : 1).
Halide ion effects in the rhodium-catalyzed allylic substitution reaction using copper(I) alkoxides and enolates
作者:P.Andrew Evans、David K. Leahy、Laura M. Slieker
DOI:10.1016/j.tetasy.2003.08.044
日期:2003.11
enolates with a copper(I) halide salt provides the requisite nucleophiles to accomplish the stereospecific rhodium-catalyzedallylic substitution. These studies demonstrate that the nature of the halide ion derived from the copper(I) salt has a profound effect on regioselectivity and enantiospecificity. This observation was attributed to the trans-effect, by virtue of an in situ modification of the catalyst