Regiodivergent hydrosilylation, hydrogenation, [2π + 2π]-cycloaddition and C–H borylation using counterion activated earth-abundant metal catalysis
作者:Riaz Agahi、Amy J. Challinor、Joanne Dunne、Jamie H. Docherty、Neil B. Carter、Stephen P. Thomas
DOI:10.1039/c8sc05391j
日期:——
The widespread adoption of earth-abundant metal catalysis lags behind that of the second- and third-row transitionmetals due to the often challenging practical requirements needed to generate the active low oxidation-state catalysts. Here we report the development of a single endogenous activation protocol across five reaction classes using both iron- and cobalt pre-catalysts. This simple catalytic
An NNN-Pincer-Cobalt Complex Catalyzed Highly Markovnikov-Selective Alkyne Hydrosilylation
作者:Shaochun Zhang、Jessica Juweriah Ibrahim、Yong Yang
DOI:10.1021/acs.orglett.8b02746
日期:2018.10.5
A new NNN pincer (amine–pyridine–imine, API) cobalt complex, which is bench-stable and is applicable for the highly efficient and regioselective hydrosilylation of terminal alkynes, is developed. A broad set of α-vinylsilanes was successfully synthesized in good to high yields with up to 98/2 Markovnikov regioselectivity. This protocol can be readily scaled up for gram-scale synthesis and demonstrates
开发了一种新型的NNN钳形(胺-吡啶-亚胺,API)钴复合物,该复合物具有台式稳定性,适用于末端炔烃的高效和区域选择性氢化硅烷化。成功地以高至高收率和高达98/2的马尔可夫尼科夫区域选择性合成了多种α-乙烯基硅烷。该方案可以很容易地按比例放大以进行克级合成,并证明迄今为止,最有效的炔烃钴催化氢化硅烷化反应的周转频率高达126 720 h –1。
Porous Organic Polymer as a Heterogeneous Ligand for Highly Regio- and Stereoselective Nickel-Catalyzed Hydrosilylation of Alkyne
A porousorganicpolymer (POL-Xantphos) was synthesized and employed as a heterogeneous ligand for selective hydrosilylation of alkynes. It exhibits high selectivity and catalytic efficiency toward a broad range of alkynes. Owing to the confinement effect of the micropore structure, POL-Xantphos was far superior to the monomeric Xantphos ligands in controlling the selectivity. By performing hydrosilylation
Cobalt-Catalyzed <i>Z</i>
-Selective Hydrosilylation of Terminal Alkynes
作者:Wei Jie Teo、Chao Wang、Ye Wei Tan、Shaozhong Ge
DOI:10.1002/anie.201700868
日期:2017.4.3
A cobalt‐catalyzed Z‐selective hydrosilylation of alkynes has been developed relying on catalysts generated from bench‐stable Co(OAc)2 and pyridine‐2,6‐diimine (PDI) ligands. A variety of functionalized aromatic and aliphatic alkynes undergo this transformation, yielding Z‐vinylsilanes in high yields with excellent selectivities (Z/E ratio ranges from 90:10 to >99:1). The addition of a catalytic amount
Geminal bis(silanes) are versatile synthetic building blocks owing to their stability and propensity to undergo a variety of transformations. However, the scarcity of catalytic methods for their synthesis limits their structural diversity and thus their utility for further applications. Herein we report a new method for synthesis of geminal bis(silanes) by means of iron-catalyzed dihydrosilylation