New Zinc Catalyst for Hydrosilylation of Carbonyl Compounds
作者:Iryna D. Alshakova、Georgii I. Nikonov
DOI:10.1055/s-0037-1611824
日期:2019.9
bonds, and thus can be useful for the synthesis of allylic alcohols from α,β-unsaturated aldehydes and ketones. A new zinc complex was synthesized and applied in the catalytichydrosilylation of carbonyl compounds. Optimization of the reaction conditions showed that the presence a substoichiometric amount of methanol accelerates the process significantly. The reaction can proceed at very low catalyst
Synthesis of silyl iron hydride <i>via</i> Si–H activation and its dual catalytic application in the hydrosilylation of carbonyl compounds and dehydration of benzamides
The hydrido silyl iron complex (o-Ph2PC6H4SiMe2)Fe(PMe3)3H (2) was obtained via the activation of the Si–H bond of the bidentate silyl ligand o-Ph2P(C6H4)SiMe2H (1) by Fe(PMe3)4. 2 showed good to excellent catalytic activity in both the reduction of aldehydes/ketones and the dehydration of benzamide. In addition, with complex 2 as a catalyst, α,β-unsaturated carbonyls could be selectively reduced to
氢化硅烷基铁络合物(o -Ph 2 PC 6 H 4 SiMe 2)Fe(PMe 3)3 H(2)是通过激活双齿甲硅烷基配体o -Ph 2 P(C)的Si–H键而获得的Fe(PMe 3)4形成6 H 4)SiMe 2 H(1)。图2在醛/酮的还原和苯甲酰胺的脱水中均显示出良好至优异的催化活性。另外,带复数2作为催化剂,α,β-不饱和羰基可以选择性地还原为相应的α,β-不饱和醇。提出了2的形成机理和催化脱水过程,并进行了部分实验验证。
Enantioselective Zinc-Catalyzed Hydrosilylation of Ketones using Pybox or Pybim Ligands
The combination of ZnEt2 and chiral pyridinebisoxazoline (pybox) or pyridinebisimidazoline (pybim) ligands catalyzed the asymmetric hydrosilylation of aryl, alkyl, cyclic, heterocyclic, and aliphatic ketones. Under mild conditions, high yields and good enantioselectivities were achieved. ESI measurements allowed for the characterization of the active catalyst.
(sp3)−H bond. It was found that complex 1 exhibited excellent catalytic activity for hydrosilylation of aldehydes and ketones. The catalytic system showed good tolerance and catalytic activity for the substrates with different functional groups on the benzene ring. It is worth mentioning that, the experimental results showed that both ketones and aldehydes could be reduced in good to excellent yields under
CpFe(CO)<sub>2</sub> anion-catalyzed highly efficient hydrosilylation of ketones and aldehydes
作者:Ke Lou、Qingyang Zhou、Qi Wang、Xingchao Fan、Xiufang Xu、Chunming Cui
DOI:10.1039/d1dt01778k
日期:——
K[CpFe(CO)2] and [NEt4][CpFe(CO)2] enabled highly efficient hydrosilylation of ketones and aldehydes with PhSiH3 to synthesize tris- and bis(alkoxy)silanes in excellent yields depending on the substituents on the carbonyl compounds. The catalyst represents one of the most efficient and practical iron catalysts for hydrosilylation of carbonyl compounds with a TOF up to 24 540 h−1.