188527-65-3Relevant articles and documents
Efficient Negishi coupling reactions of aryl chlorides catalyzed by binuclear and mononuclear nickel-N-heterocyclic carbene complexes
Xi, Zhenxing,Zhou, Yongbo,Chen, Wanzhi
, p. 8497 - 8501 (2008)
(Chemical Equation Presented) We describe the first nickel-N-heterocyclic carbene catalyzed Negishi cross-coupling reaction of a variety of unactivated aryl chlorides, heterocyclic chlorides, aryl dichlorides, and vinyl chloride. The mononuclear and binuclear nickel-NHC complexes supported by heteroarene-functionalized NHC ligands are found to be highly efficient for the coupling of unactivated aryl chlorides and organozinc reagents, leading to biaryls and terphenyls in good to excellent yields under mild conditions. For all aryl chlorides, the binuclear nickel catalysts show activities higher than those of mononuclear nickel complexes because of possible bimetallic cooperative effect.
Triorganoindium reagents in Rh-catalyzed C–H activation/C–C cross-coupling reactions of 2-arylpyridines
Riveiros, Ricardo,Tato, Rubén,Sestelo, José Pérez,Sarandeses, Luis A
, (2018/07/13)
The activation of C–H bonds through catalytic reactions using transition metals is an important challenge in organic chemistry in which the intermediates are related to those produced in the classical cross-coupling reactions. As part of our research program devoted to the development of metal-catalyzed reactions using indium organometallics, a protocol for the C–H activation and C–C coupling of 2-arylpyridines with triorganoindium reagents under Rh(I) catalysis is reported. Under the optimized conditions, we found that Me3In and Ar3In reagents reacted with 2-arylpyridines and related compounds in the presence of Rh(PPh3)3Cl, in PhCl/THF (9:1), at 120?C for 48 h, to afford the ortho-coupling products in moderate to good yields. The nitrogen atom in the pyridine ring acts as a directing group to assist the functionalization at the ortho position of the aryl group forming a new C–C bond at this position.
Synthesis, characterization, and catalytic activity of nickel(II) alkyl complexes supported by pyrrole-diphosphine ligands
Venkanna, Gopaladasu T.,Tammineni, Swetha,Arman, Hadi D.,Tonzetich, Zachary J.
, p. 4656 - 4663 (2013/09/23)
The organometallic Ni(II) chemistry of the pyrrole-based pincer ligands (P2RPyr)- (P2RPyr = 2,5-(R2PCH2)2C4H2N, R = Ph, Cy) is reported. Reactions of Grignard reagents with [NiCl(P 2RPyr)] afford a variety of alkyl and aryl complexes (methyl, ethyl, benzyl, phenyl, and allyl) that all display square-planar geometries about nickel. The hydride complex [NiH(P2 CyPyr)] can also prepared either through treatment of [NiCl(P 2CyPyr)] with LiHBEt3 or by reaction of H(P2RPyr) with [Ni(COD)2] (COD = 1,4-cyclooctadiene). Reactions of the methyl and hydride complexes with CO and CO2, respectively, evince clean migratory insertion chemistry of the Ni-C and Ni-H bonds. Both the alkyl and chloride complexes are active catalysts for the Kumada coupling of aryl chlorides and aryl or alkyl Grignard reagents at room temperature. The solid-state structures of several of the complexes are reported.
