Chiral bis(oxazolinylphenyl)amines proved to be efficient auxiliary ligands for iron and cobalt catalysts with high activity for asymmetrichydrosilylation of ketones and asymmetric conjugate hydrosilylation of enones.
Asymmetric Transfer Hydrogenation of (Hetero)arylketones with Tethered Rh(III)–<i>N</i>-(<i>p</i>-Tolylsulfonyl)-1,2-diphenylethylene-1,2-diamine Complexes: Scope and Limitations
A series of new tethered Rh(III)/Cp* complexes containing the N-(p-tolylsulfonyl)-1,2-diphenylethylene-1,2-diamine ligand have been prepared, characterized, and evaluated in the asymmetric transfer hydrogenation (ATH) of a wide range of (hetero)aryl ketones. The reaction was performed under mild conditions with the formic acid/triethylamine (5:2) system as the hydrogen source and provided enantiomerically
Asymmetric Reduction of Electron-Rich Ketones with Tethered Ru(II)/TsDPEN Catalysts Using Formic Acid/Triethylamine or Aqueous Sodium Formate
作者:Rina Soni、Thomas H. Hall、Benjamin P. Mitchell、Matthew R. Owen、Martin Wills
DOI:10.1021/acs.joc.5b00990
日期:2015.7.2
The asymmetric transfer hydrogenation (ATH) of ketones under aqueous conditions using tethered Ru(II)/η6-arene/diamine catalysts is described, as is the ATH of electron-rich substrates containing amine and methoxy groups on the aromatic rings. Although such substrates are traditionally challenging ones for ATH, the tethered catalysts work very efficiently. In the case of amino-substituted ketones,
activities (up to 9800 TON; TON=turnover number), broad substrate scope (81 examples), good functional‐group tolerance, and excellent enantioselectivities (85–98 % ee) in the hydrogenation of various ketones. These aspects are rare in earth‐abundant metal catalyzed hydrogenations. The utility of the protocol have been demonstrated in the asymmetric synthesis of a variety of key intermediates for chiral drugs
已经开发了一系列含有基于核苷的手性钳式配体的Mn I配合物,这些配合物具有模块化和可调的结构。该配合物在各种酮的氢化反应中显示出前所未有的高活性(高达9800 TON; TON =周转数),广泛的底物范围(81个实例),良好的官能团耐受性和出色的对映选择性(85-98%ee)。这些方面在稀土金属催化的氢化反应中很少见。该协议的实用性已在手性药物的多种关键中间体的不对称合成中得到证明。初步的机理研究表明,底物与催化剂相互作用的外层模式可能主导了催化作用。
Retracted: The Manganese(I)‐Catalyzed Asymmetric Transfer Hydrogenation of Ketones: Disclosing the Macrocylic Privilege
作者:Alessandro Passera、Antonio Mezzetti
DOI:10.1002/anie.201912605
日期:2020.1.2
The bis(carbonyl) manganese(I) complex [Mn(CO)2 (1)]Br (2) with a chiral (NH)2 P2 macrocyclic ligand (1) catalyzes the asymmetrictransferhydrogenation of polar double bonds with 2-propanol as the hydrogen source. Ketones (43 substrates) are reduced to alcohols in high yields (up to >99 %) and with excellent enantioselectivities (90-99 % ee). A stereochemical model based on attractive CH-π interactions