Rhodium-Catalyzed Enantioselective Decarboxylative Alkynylation of Allenes with Arylpropiolic Acids
作者:Christian P. Grugel、Bernhard Breit
DOI:10.1021/acs.orglett.7b04035
日期:2018.2.16
A rhodium-catalyzed chemo-, regio-, and enantioselective intermolecular decarboxylative alkynylation of terminal allenes with arylpropiolic acids is reported. Employing a Rh(I)/(R)-Tol-BINAP catalytic system, branched allylic 1,4-enynes were obtained under mild conditions. The overall utility of this protocol is exemplified by a broad functional group compatibility.
Enantioselective Rhodium-Catalyzed Synthesis of Branched Allylic Amines by Intermolecular Hydroamination of Terminal Allenes
作者:Michael L. Cooke、Kun Xu、Bernhard Breit
DOI:10.1002/anie.201206594
日期:2012.10.22
Branching out: The rhodium‐catalyzed enantioselectivehydroamination of monosubstituted allenes with anilines permits the atom‐economic synthesis of valuable branchedallylicamines. In contrast to previous linear selective allenehydroaminations, a RhI/Josiphos catalyst system (see scheme; cod=1,5‐cyclooctadiene, DCE=1,2‐dichloroethane) allows branchedallylicamines to be obtained with perfect regioselectivity
分支:苯胺对铑取代的单取代烯的对映选择性氢化胺化反应可实现原子经济的有价值的支链烯丙基胺的合成。与以前的线性选择性丙二烯加氢胺化反应相比,Rh I / Josiphos催化剂体系(参见方案; cod = 1,5-环辛二烯,DCE = 1,2-二氯乙烷)可以以理想的区域选择性,高收率获得支链烯丙基胺。和良好的对映选择性。
Enantioselective Synthesis of Branched Allylic Esters via Rhodium-Catalyzed Coupling of Allenes with Carboxylic Acids
We report on the first intermolecular asymmetric catalytic regio- and enantioselective addition of carboxylic acids to terminalallenes to form valuable branchedallylic esters, employing a rhodium(I)/(R,R)-DIOP catalyst system.
Atom‐Economic, Regiodivergent, and Stereoselective Coupling of Imidazole Derivatives with Terminal Allenes
作者:Kun Xu、Niels Thieme、Bernhard Breit
DOI:10.1002/anie.201309126
日期:2014.2.17
Pd‐catalyzed regiodivergent and stereoselective intermolecular coupling reactions of imidazolederivatives with mono‐substituted allenes are herein reported. Using a RhI/Josiphos system, perfect regioselectivities and high enantiomeric excess were obtained, while a PdII/dppf system gave linear products with high regioselectivities and high E/Z selectivities. This method permits the atomeconomic synthesis
本文报道了新的Rh和Pd催化的咪唑衍生物与单取代的Allenes的区域发散和立体选择性分子间偶联反应。使用Rh I / Josiphos系统,可以获得完美的区域选择性和高对映体过量,而Pd II / dppf系统则可提供具有高区域选择性和高E / Z选择性的线性产物。该方法允许原子经济地合成有价值的支链和线性烯丙基咪唑衍生物。