Bench-Stable Cobalt Pre-Catalysts for Mild Hydrosilative Reduction of Tertiary Amides to Amines and Beyond
作者:Alibek Nurseiit、Jaysan Janabel、Kristina A. Gudun、Aishabibi Kassymbek、Medet Segizbayev、Tulegen M. Seilkhanov、Andrey Y. Khalimon
DOI:10.1002/cctc.201801605
日期:2019.1.23
unsaturated organic molecules, including the normally challenging reduction of amides to amines. With regard to hydrosilative reduction of amides even more effective and activator free catalytic systems can be generated from the bench‐stable, commercially available Co(acac)2 and Co(OAc)2 with dpephos and PPh3 ligands. These systems operate under mild conditions (<100 °C), with many examples of room temperature
Cobalt-Catalyzed (<i>E</i>)-Selective<i>anti</i>-Markovnikov Hydrosilylation of Terminal Alkynes
作者:Caizhi Wu、Wei Jie Teo、Shaozhong Ge
DOI:10.1021/acscatal.8b01410
日期:2018.7.6
regioselective and stereoselective hydrosilylation of terminalalkynes with catalysts generated from bench-stable Co(acac)2 and bisphoshpine ligands. The cobalt catalyst precursors are activated by the reaction with hydrosilanes, and air-sensitive activators, such as Grignard reagents or NaBHEt3, are not required for catalyst activation. A wide range of aromatic and aliphatic terminalalkynes underwent this
Importance of co-donor field strength in the preparation of tetradentate α-diimine nickel hydrosilylation catalysts
作者:Tyler M. Porter、Gabriel B. Hall、Thomas L. Groy、Ryan J. Trovitch
DOI:10.1039/c3dt52419a
日期:——
Although bis(α-diimine)Ni complexes were prepared when amine-substituted chelates were added to Ni(COD)2, the incorporation of strong-field phosphine donors allowed the isolation of (κ4-N,N,P,P-DI)Ni hydrosilylation catalysts. The crystallographic investigation of two different (κ4-N,N,P,P-DI)Ni compounds revealed that the geometry about nickel influences the observed degree of α-diimine reduction.
A concise strategy for the synthesis of vinylsilanes from an iron-catalyzed regio- and stereoselective hydrosilylation of terminalalkynes has been developed. The catalyst and reagents are commercially available and easy to handle, providing a simple and practical method for iron-catalyzed anti-Markovnikov hydrosilylation with a good functional group tolerance.
(E)-selective hydrosilylation of alkynes with PhSiH3 has been developed for the synthesis of (E)-β-vinylsilanes with high regio- and stereoselectivity and wide functional group tolerance. It is the first report of using porous organic polymer as a recyclable regio- and stereoselective and efficient ligand in hydrosilylation reactions in which the polymer could be recycled numerous times in a continuous flow