Just a little bit: The 1/FeCl2 complex was activated in the presence of Zn and exhibited catalytic activity for the hydrosilanereduction of ketones to give the S‐configured alcohol. In contrast, the mixed‐catalyst system of 1 and Fe(OAc)2 provides the R enantiomer. This approach provides both enantiomers from a single chiral source by the addition of a small amount of Zn.
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。
Kinetic resolution of racemic benzofused alcohols catalysed by HMFO variants in presence of natural deep eutectic solvents
作者:Gonzalo de Gonzalo、Nikola Lončar、Marco Fraaije
DOI:10.1080/10242422.2022.2038582
日期:2023.3.4
selective oxidation of alcohols employing oxygen as mild oxidant with no requirement of expensive organic cofactors. This wild-type HMFO biocatalyst and an engineered thermostable variant have been tested in the kinetic resolution of different benzofused alcohols. The use of natural deep eutectic solvents was also explored in HMFO-catalysed oxidation of alcohols. The oxidation of racemic 1-indanol showed
Chemo‐ and Enantioselective Photoenzymatic Ketone Reductions Using a Promiscuous Flavin‐dependent Nitroreductase
作者:Alejandro Prats Luján、Mohammad Faizan Bhat、Thangavelu Saravanan、Gerrit J. Poelarends
DOI:10.1002/cctc.202200043
日期:2022.4.22
The enantioselective photoenzymatic reduction of a wide variety of ketones to the corresponding alcohols using the promiscuous nitroreductase BaNTR1 is reported. This flavoenzyme not only shows outstanding enantioselectivity but also remarkably high chemoselectivity, promoting the photoenzymatic reduction of various α,ß-unsaturated ketones to give the desired enantioenriched alcohols without reducing
first time the highly regio- and enantioselective ring opening of a biobased itaconic anhydride catalyzed by the Pseudomonas cepacialipase (PCL) in tert-butyl methyl ether (TBME) at room temperature. This method is easy, efficient and eco-friendly and can be performed in one step with a series of highly valuable monoester itaconates (achiral or enantioenriched) using various alcohols as nucleophiles