E- and Z-, di- and tri-substituted alkenyl nitriles through catalytic cross-metathesis
作者:Yucheng Mu、Thach T. Nguyen、Ming Joo Koh、Richard R. Schrock、Amir H. Hoveyda
DOI:10.1038/s41557-019-0233-x
日期:2019.5
the development of several efficient catalytic cross-metathesis strategies, which provide direct access to a considerable range of Z- or E-di-substituted cyano-substituted alkenes or their corresponding tri-substituted variants. Depending on the reaction type, a molybdenum-based monoaryloxide pyrrolide or chloride (MAC) complex may be the optimal choice. The utility of the approach, enhanced by an easy
[EN] PROCESS FOR HYDROCYANATION OF TERMINAL ALKYNES<br/>[FR] PROCÉDÉ D'HYDROCYANATION D'ALCYNES TERMINAUX
申请人:STUDIENGESELLSCHAFT KOHLE MBH
公开号:WO2018210631A1
公开(公告)日:2018-11-22
The present invention refers to a process for a Rh-catalyzed Anti-Markovnikov hydrocyanation of terminal alkynes which process discloses, for the first time, the highly stereo- and regio-selective hydrocyanation of terminal alkynes to furnish E- configured alkenyl nitriles and the catalyst used in the present process.
Rh-Catalyzed Anti-Markovnikov Hydrocyanation of Terminal Alkynes
作者:Fei Ye、Junting Chen、Tobias Ritter
DOI:10.1021/jacs.7b03749
日期:2017.5.31
We report the first highly stereo- and regioselective hydrocyanation of terminal alkynes to furnish E-configured alkenyl nitriles. Acrylonitriles can be accessed on gram scale with broad substrate scope and functional group tolerance. The hydrocyanation reaction employs acetone cyanohydrin as a practical alternative to HCN gas.
我们报告了第一个高度立体和区域选择性的末端炔烃氢氰化反应,以提供 E 构型的烯基腈。丙烯腈可以在克级获得,具有广泛的底物范围和官能团耐受性。氢氰化反应使用丙酮氰醇作为 HCN 气体的实用替代品。
Stereoselective Olefination of N-Sulfonyl Imines with Stabilized Phosphonium Ylides for the Synthesis of Electron-Deficient Alkenes
作者:Fan Fang、Yuan Li、Shi-Kai Tian
DOI:10.1002/ejoc.201001379
日期:2011.2
alkenes in moderate to excellent yields from readily accessible N-sulfonyl imines and stabilized phosphoniumylides. Significantly, the olefination reaction of N-sulfonylimines with nitrile-stabilized phosphoniumylides affords an array of α,β-unsaturated nitriles with high Z selectivity, and the reactions with ester-, amide-, and ketone-stabilized phosphoniumylides afford α,β-unsaturated esters, amides
已经开发了一种前所未有的方案,用于从易于获得的 N-磺酰基亚胺和稳定的鏻叶立德以中等至优异的产率立体选择性合成结构多样的缺电子烯烃。值得注意的是,N-磺酰亚胺与腈稳定的鏻叶立德的烯化反应提供了一系列具有高 Z 选择性的 α,β-不饱和腈,并且与酯、酰胺和酮稳定的鏻叶立德的反应提供了 α,β -分别具有高 E 选择性的不饱和酯、酰胺和酮。反应混合物的光谱分析和中间体的捕获允许提出合理的机制。初始亚胺/叶立德加成导致形成环化形成 1 的甜菜碱,2-氮杂膦烷随后消除亚氨基膦以产生烯烃。对于缺电子的 1,2-二取代烯烃的合成,甜菜碱中吸电子基团的存在允许通过质子转移在其两种非对映异构体之间快速相互转化。烯烃合成的 Z/E 选择性由两种甜菜碱非对映异构体形成相应的 1,2-氮杂膦非对映异构体的不同速率决定。相比之下,合成缺电子三取代烯烃的 Z/E 选择性源于稳定的鏻叶立德与 N-磺酰基亚胺的非对映选
Synthetic studies related to diketopyrrolopyrrole (DPP) pigments. Part 1: The search for alkenyl-DPPs. Unsaturated nitriles in standard DPP syntheses: a novel cyclopenta[c]pyrrolone chromophore
methacrylonitrile give 4,4-bis(cyanoethyl) and 4,4-bis(2-cyanopropyl) derivatives, and cinnamonitrile, substituted cinnamonitriles and 3-(2-thienyl)acrylonitrile give deep red 3-aryl-5-cyano-4-hydroxy-2H-cyclopenta[c]pyrrol-1-ones. These ambident nucleophiles may undergo N- and either O- or C-alkylation according to the alkylating agent used.
4,5-二氢-5-氧代-2-苯基吡咯-3-羧酸乙酯的阴离子与丙烯腈和各种二烯的狄尔斯-阿尔德加合物的反应很少产生预期的DPP衍生物。与环己-3-烯腈的反应提供了一个值得注意的例外:所生成的环己烯基-DPP的热解产生了丁二烯和不纯的3-乙烯基-6-苯基-DPP,后者是热不稳定的。当上述阴离子与α,β-不饱和腈反应时,迈克尔加成反应占主导:丙烯腈和甲基丙烯腈产生4,4-双(氰基乙基)和4,4-双(2-氰基丙基)衍生物,以及肉桂腈,取代的肉桂腈和3-( 2-噻吩基)丙烯腈得到深红色的3-芳基-5-氰基-4-羟基-2 H-环戊[ c ]吡咯-1-酮。这些亲核试剂两可可经历Ñ-和根据所用烷基化剂的O-或C-烷基化。