A Convoluted Polyvinylpyridine‐Palladium Catalyst for Suzuki‐Miyaura Coupling and C−H Arylation
作者:Aya Ohno、Takuma Sato、Toshiaki Mase、Yasuhiro Uozumi、Yoichi M. A. Yamada
DOI:10.1002/adsc.202000742
日期:2020.11.4
and reusablesupportedcatalysts for Suzuki‐Miyaura coupling and catalytic C−H arylation is important for fundamental and applied chemistry, with these reactions being used to produce medical compounds and functional materials. Herein, we found that a mesoporous composite made of a linear poly(4‐vinylpyridine) and tetrachloropalladate acted as a dual‐mode catalyst for a variety of cross‐coupling reactions
of an air‐stable, robust palladium/tridentate phosphane catalyst in direct CH and CCl activation reactions is reported (see scheme; DMAc=N,N‐dimethylacetamide, TBAB=tetra‐n‐butylammonium bromide). Electron‐rich, electron‐poor, and polysubstituted furans (X=O), thiophenes (X=S), pyrroles (X=NR5), and thiazoles were arylated with chloroarenes in the presence of the catalyst.
穿上它的环:在直接C中的使用对空气稳定的,坚固的钯/三齿磷烷催化剂 H和13 C 氯活化反应报道(参见方案;的DMAc = Ñ,Ñ二甲基乙酰胺,TBAB =四Ñ -丁基溴化铵)。在催化剂存在下,富电子,贫电子和多取代的呋喃(X = O),噻吩(X = S),吡咯(X = NR 5)和噻唑被氯芳烃芳基化。
Palladium-Catalyzed Direct Arylation of Heteroaromatic Compounds: Improved Conditions Utilizing Controlled Microwave Heating
作者:Mostafa Baghbanzadeh、Christian Pilger、C. Oliver Kappe
DOI:10.1021/jo201516v
日期:2011.10.7
A versatile and rapid microwave-assisted procedure for the palladium-catalyzed direct arylation of heterocycles by arylbromides and heteroarylbromides is described. This novel protocol features short coupling times (10–60 min) and low catalyst loadings (1 mol %) and allows the successful arylation of previously unreactive heterocyclic substrates.
Well-Defined Palladium N-Heterocyclic Carbene Complexes: Direct C–H Bond Arylation of Heteroarenes
作者:Anuj Kumar、Manoj Kumar、Akhilesh K. Verma
DOI:10.1021/acs.joc.0c02024
日期:2020.11.6
A series of palladium N-heterocycliccarbene (NHC) complexes of type trans-(NHC)PdCl2L} (L = C5H5N, 3-ClC5H4N, and PPh3) (3–5) have been developed as efficient precatalysts for direct C–H bond arylation of various heteroarenes. In particular, an in situ generated new NHC ligand derived from 1,3-di-(2,6-diethylphenyl)acenaphtho[1,2-d] imidazolium} chloride (2) is used for the stabilization of the
反式-(NHC)PdCl 2 L}(L = C 5 H 5 N,3-ClC 5 H 4 N和PPh 3)的一系列钯N-杂环卡宾(NHC)配合物(3 – 5)已经开发出作为各种杂芳烃直接C–H键芳基化的有效预催化剂。特别地,使用由1,3-二-(2,6-二乙基苯基)ac [1,2- d ]咪唑鎓}氯化物(2)衍生的原位生成的新NHC配体来稳定钯金属中心。在筛选出的钯预催化剂中(3 – 5),最活跃的PEPPSI主题复合物(3)已成功用于各种杂芳烃和芳基溴化物的直接C–H键芳基化。在整个标准反应条件下,芳基溴化物和杂芳烃上的一系列官能团均可轻松获得各种芳基化杂环化合物。重要的是,该协议的实用性通过有效合成雷洛昔芬(一种选择性雌激素受体调节剂)的前体来证明。
Direct C–H/C–H cross-coupling of benzimidates with heteroarenes to access biheteroaryl-2-carbonitriles
A rhodium(iii)-catalyzed oxidative C–H/C–H cross-coupling of benzimidates with various heteroarenes has been devloped to directly furnish biheteroaryl-2-carbonitriles.