N-Heterocyclic carbene rhodium(<scp>i</scp>) complexes containing an axis of chirality: dynamics and catalysis
作者:Maria Cristina Cassani、Marta Anna Brucka、Cristina Femoni、Michele Mancinelli、Andrea Mazzanti、Rita Mazzoni、Gavino Solinas
DOI:10.1039/c3nj01620j
日期:——
Novel rhodium(i) complexes [RhCl(NBD)(NHC)] [NHC = 1-benzyl-3-R-imidazolin-2-ylidene; R = Me, Bz, Tr, tBu]: determination of the rotation barriers about the Rh-carbene and catalytic activity in the hydrosilylation of terminal alkynes.
新型铑(i)配合物 [RhCl(NBD)(NHC)] [NHC = 1-苄基-3-R-咪唑啉-2-基醇; R = 甲基,苯甲酰,三氟甲基,t丁基]:确定Rh-卡宾的旋转阻 barriers 以及在顺烯烃的氢硅烷化反应中的催化活性。
Carboxylate-Assisted β-(<i>Z</i>) Stereoselective Hydrosilylation of Terminal Alkynes Catalyzed by a Zwitterionic Bis-NHC Rhodium(III) Complex
作者:Raquel Puerta-Oteo、Julen Munarriz、Víctor Polo、M. Victoria Jiménez、Jesús J. Pérez-Torrente
DOI:10.1021/acscatal.0c01582
日期:2020.7.2
catalyst for the hydrosilylation of terminal alkynes with excellent regio- and stereoselectivity toward the less thermodynamically stable β-(Z)-vinylsilane isomer under mild reaction conditions. A broad range of linear 1-alkynes, cycloalkyl acetylenes, and aromatic alkynes undergo the hydrosilylation with HSiMe2Ph to afford the corresponding β-(Z)-vinylsilanes in quantitative yields in short reaction times
hydrosilylation of terminal alkynes with HSiMe2Ph has been investigated with PhC≡CH, TolC≡CH, nBuC≡CH, Et3SiC≡CH, and (CPh2OH)C≡CH as substrates. The steric hindrance on the N-heterocyclic ligand and on the alkyne substrates affects conversion and selectivity: for the former the best results were achieved employing the less encumbered 3a catalyst with TolC≡CH, whereas by employing hindered alkynes such as Et3SiC≡CH
酰胺官能化的咪唑鎓盐[BocNHCH 2 CH 2 ImR ] X(R = Me,X = I,1a ; R =苄基,X = Br,1b ; R =三苯甲基,X = Cl,1c)带有越来越大的N-通过(2-咪唑-1-基-乙基)氨基甲酸叔丁酯的直接烷基化,高产率地制备烷基取代基。1c是结晶固体,其特征还在于X射线衍射。这些盐是合成铑(I)配合物[Rh(NBD)X(NHC)]的前体(NHC = 1-(2-NHBoc-乙基)-3-R-咪唑啉-2-亚基; X = Cl, R = Me(3a),R =苄基(3b),R =三苯甲基(3c); X = I,R = Me(4a))。所有的配合物都表现出绕金属碳烯键旋转受限的现象。然而,尽管为3a,b和4a计算的旋转势垒与实验值匹配,但出乎意料的是,对于3c而言,情况并非如此,因为3c的实验值等于化合物3b的实验值(58.6 kJ mol –1),并且相对于所计算的值较小(100
New organoplatinum (IV) complex with quaterpyridine ligand: Synthesis, structure and its catalytic activity in the hydrosilylation of styrene and terminal alkynes
The reaction of ligand L with PtCl2 leads to a novel structural motif of octahedral ortho-metalated complex of formula [Pt(L-H)Cl-3] I. This result is a consequence of drastic conditions of reaction and preferred Pt(IV) octahedral coordination geometry. The new compound has been characterised on the basis of the spectroscopic data in solution, and its structure confirmed in the solid state by X-ray crystallography (1a-[Pt(L-H)Cl-3].MeOH, 1b-[Pt(LH)Cl-3]center dot C6H5CH3). This article reports organoplatinum (IV) complex 1 as effective and highly selective catalyst precursor in the hydrosilylation of styrene and terminal alkynes. (C) 2013 Elsevier B.V. All rights reserved.
Highly selective hydrosilylation of olefins and acetylenes by platinum(0) complexes bearing bulky N-heterocyclic carbene ligands
作者:P. Żak、M. Bołt、M. Kubicki、C. Pietraszuk
DOI:10.1039/c7dt04392a
日期:——
Platinum complexes bearing bulky N-heterocycliccarbene (NHC) ligands, i.e., [Pt(IPr*)(dvtms)] (where, IPr* = 1,3-bis2,6-bis(diphenylmethyl)-4-methylphenyl}imidazol-2-ylidene) and [Pt(IPr*OMe)(dvtms)] (where, IPr*OMe = 1,3-bis2,6-bis(diphenylmethyl)-4-methoxyphenyl}imidazol-2-ylidene, dvtms = divinyltetramethyldisiloxane) catalyse nearly quantitatively and highly or completely the selective hydrosilylation