Selective synthesis of (E)-triethyl(2-arylethenyl)silane derivatives by reaction of aryl bromides with triethyl vinylsilane catalysed by a palladium–tetraphosphine complex
摘要:
Cis, cis, cis-1,2,3,4-tetrakis(diphenylphosphinomethyl)cyclopentane/0.5[PdCI(C3H5)](2) system catalyses the Heck reaction of vinylsilane derivatives with a range of aryl bromides with high ratio substrate/catalyst in good yields. The formation of mixtures of styrene, (E)-triethyl(2-arylethenyl)sitane and triethyl(1-arylethenyl)silane derivatives was observed in some cases. Very high selectivities (up to 100%) in favour of the formation of (E)-triethyl(2-arylethenyl)silane derivatives were obtained in the presence of sodium acetate as base. With other bases such as potassium carbonate, the formation of large amounts of styrene derivatives was observed. The reaction tolerates several functions such as fluoro, trifluoromethyl, methoxy, dimethylamino, acetyl, formyl, benzoyl, carboxylate, nitro or nitrile. Moreover, turnover numbers up to 10,000 can be obtained for this reaction. (c) 2005 Elsevier B.V. All rights reserved.
Palladium(II) Complexes of a Neutral CCC-Tris(N-heterocyclic carbene) Pincer Ligand: Synthesis and Catalytic Applications
作者:David Rendón-Nava、Deyanira Angeles-Beltrán、Arnold L. Rheingold、Daniel Mendoza-Espinosa
DOI:10.1021/acs.organomet.1c00324
日期:2021.7.12
tris-azolium precursor 1 with palladium acetate under thermal conditions provided a CCC-pincer palladium(II) complex (2) bearing three NHCs (one imidazolylidene and two triazolylidenes) and one iodide ligand. Further treatment of complex2 with an excess of AgSbF6 generates tris(carbene) dicationic palladium complex3 in which the iodine ligands are exchanged with SbF6 anions and the metal center is stabilized
adienyl iridium(III) metallacycles catalyse the hydrosilylation of alkynes using triethylsilane and no additive. The reactions proceed rapidly and efficiently at low catalyst loadings and under mild reaction conditions. If catalyses starting from terminalalkynes lead selectively to (Z)-alkenylsilanes in high yields, reactions are less efficient and selective starting from internal alkynes due to steric
Rhodium(I) Complexes Bearing Hydroxyl‐Functionalized 1,2,3‐Triazolylidenes and Their Catalytic Application
作者:Agustín A. de la Fuente‐Olvera、Franciso J. Ruiz‐Mendoza、José M. Vásquez‐Pérez、Myriam Meléndez‐Rodríguez、Alejandro Álvarez‐Hernández、Verónica Salazar‐Pereda、Daniel Mendoza‐Espinosa
DOI:10.1002/ejic.202200401
日期:2022.10.26
We report the synthesis and full characterization of a novel series rhodium(I) complexes (3 a–c) supported by hydroxyl-functionalized 1,2,3-triazolylidenes. Their application as catalysts in the 1,4-addition of boronic acid to 2-cyclohexenone and the hydrosilylation of terminal alkynes is described.
Rhodium-Catalyzed Alkenylation of Nitriles via Silicon-Assisted C−CN Bond Cleavage
作者:Yusuke Kita、Mamoru Tobisu、Naoto Chatani
DOI:10.1021/ol100481h
日期:2010.4.16
Rhodium-catalyzed Mizoroki-Heck type reaction of nitriles via the cleavage of C-C bonds is described. Orthogonal and iterative functionalizations of arenes were also demonstrated by combining the present and conventional halide-based cross-coupling reactions.