Synthesis and catalytic applications of palladium N-heterocyclic carbene complexes as efficient pre-catalysts for Suzuki–Miyaura and Sonogashira coupling reactions
excellent catalytic activities as compared to 2a–c, 3a–c, and the well-known systems for the palladium-catalysed Sonogashira reaction. The reactivity of 4a–c in these preliminary Sonogashira coupling tests seems to be higher than that of previously reported catalyticsystems based on Pd(NHC) moieties. These new palladium NHC complexes are among the first reported palladium catalysts that are efficient for
Palladium-catalyzed deacetonative coupling of aryl propargylic alcohols with aryl chlorides in water
作者:Feng Chang、Yanping Liu
DOI:10.1080/00397911.2017.1297457
日期:2017.5.19
propargylic alcohols with aryl chlorides has been developed. The reaction occurs smoothly in neat water with 2 mol% PdCl2 as catalyst, and various synthetically useful functional groups, including ether, aldehyde, ketone, and heterocyclics, are well tolerated. Moreover, the reaction could proceed through a consecutive Sonogashira/deacetonative process using 2-methyl-3-butyn-2-ol and aryl chlorides as coupling
A poly(ethylene glycol) (PEG) linked ortho‐MeO‐phenyldicyclohexylphosphine (MeO‐WePhos) ligand has been synthesized to promote Pd‐catalyzed carbon‐carbon bondformation by cross‐couplings including Sonogashira, Heck, Hiyama and Stille reactions, providing corresponding (hetero)aryl substituted alkynes, alkenes and bi(hetero)aryls in good to excellent isolated yields with low Pd loadings. Facilitated
type of heterogeneous palladium catalyst, PdMgAl‐LDH, was facilely prepared by the immobilization of Pd2+ species in the layers of a Mg‐Al layered double hydroxide (LDH) with co‐precipitation, and then fully characterized by using powder XRD, thermogravimetric differential thermal analysis, TEM, energy‐dispersive X‐ray spectroscopy, and X‐ray photoelectron spectroscopy techniques. These catalysts can efficiently
Palladacycle-Catalyzed Decarboxylative Coupling of Alkynyl Carboxylic Acids with Aryl Chlorides under Air
作者:Xiang Li、Fan Yang、Yangjie Wu
DOI:10.1021/jo400574d
日期:2013.5.3
palladacycle-catalyzed decarboxylative coupling of alkynyl carboxylic acids with arylchlorides was developed. The reaction could proceed smoothly in air within 3 h under optimized reaction conditions (1 mol % of palladacycle, 4 mol % of Xphos, 2.0 equiv of K2CO3 in xylene/H2O), affording the corresponding internal alkynes in mostly good to excellent yields. Remarkably, this result represents the first
开发了一种高效,实用的协议,用于戊四环催化炔基羧酸与芳基氯化物的脱羧偶联。在优化的反应条件(1 mol%的Palladacycle,4 mol%的Xphos,2.0当量的K 2 CO 3在二甲苯/ H 2 O中)下,反应可以在3小时内在空气中平稳进行,从而提供了大部分良好的相应内部炔烃达到优异的产量。值得注意的是,该结果代表了使用贫电子,电子中性,甚至无活性的位阻富电子的芳基氯化物作为起始原料的这种脱羧交叉偶联的第一个成功实例。