Late-Stage Generation of Bidentate η<sup>3</sup>-Benzophosphorine–Phosphino Ligands from a Rhodium PC<sub>carbene</sub>P Pincer Complex and Their Use in the Catalytic Hydrosilylation of Alkynes
作者:Qingyang Wang、Hendrik Tinnermann、Shaun Tan、Rowan D. Young
DOI:10.1021/acs.organomet.9b00314
日期:2019.10.14
PCcarbeneP pincercomplex (1) was reacted with a range of alkynes to generate complexes 2a–e and 4a–f featuring a bidentate η3-benzophosphorine–phosphino ligand PC3R1,R2(P)}. As such, a variety of electronic and steric components could be incorporated into the PC3R1,R2(P) ligand at a late synthetic stage. These complexes were found to be competent catalysts for the hydrosilylation of alkynes, providing
(E)-adduct. The [Rh-Pd] heterogeneous catalyst also showed a higher chemoselectivity than the homogeneous catalytic combination, and no detrimental formation of Sonogashira side product was observed due to an ionic-gel-mediated kinetic modulation. To illustrate its scope and limitations, the described one-pot bimetallic catalytic sequence was extended to functionalized terminal alkynes and various iodide
<i>N</i>-heterocyclic carbene platinum complexes functionalized with a polyether chain and silyl group: Synthesis and application as a catalyst for hydrosilylation
GRAPHICAL ABSTRACT ABSTRACT The synthesis and characterization of new N-heterocycliccarbeneplatinum(II) complexes functionalized with a polyether chain and silyl group are described. In addition, their application towards the catalytic hydrosilylation of unsaturated carbon–carbon bonds, including alkenes, alkynes, vinyl ether, and unsaturated esters, is reported. These new complexes exhibit both
图形摘要 摘要描述了用聚醚链和甲硅烷基官能化的新型 N-杂环卡宾铂 (II) 配合物的合成和表征。此外,还报道了它们在不饱和碳-碳键(包括烯烃、炔烃、乙烯基醚和不饱和酯)的催化氢化硅烷化中的应用。这些新的配合物表现出优异的催化活性和氢化硅烷化选择性。催化系统可循环使用 >27 次。
RhCl(PPh<sub>3</sub>)<sub>3</sub>/NaI Catalyst System for Hydrosilylation of 1-Alkynes: Stereodivergent Syntheses of E- and Z-Alkenylsilanes with Heteroatom Substituents on Silicon
Both (E)- and (Z)-alkenylsilanes are synthesized by the reaction of hydrosilanes and 1-alkynes catalyzed by RhCl(PPh3)3/NaI or RhI(PPh3)3 highly selectively.
Efficient cross-metathesis of vinylsilanes, carrying a large spectrum of different substituents at silicon, with various olefins in the presence of the first and second generation Grubbs catalyst and Hoveyda–Grubbs catalyst is described. On the basis of the results of equimolar reactions of vinylsilanes with ruthenium alkylidene complexes and experiments with deuterium-labelled reagents, a general