Bovine serum albumin–cobalt(<scp>ii</scp>) Schiff base complex hybrid: an efficient artificial metalloenzyme for enantioselective sulfoxidation using hydrogen peroxide
An artificial metalloenzyme (BSA–CoL) based on the incorporation of a cobalt(II) Schiffbase complex CoL, H2L = 2,2′-[(1,2-ethanediyl)bis(nitrilopropylidyne)]bisphenol} with bovine serum albumin (BSA) has been synthesized and characterized. Attention is focused on the catalytic activity of this artificial metalloenzyme for enantioselective oxidation of a variety of sulfides with H2O2. The influences
人工金属酶(BSA–CoL),其基于钴(II)Schiff碱络合物CoL,H 2 L = 2,2'-[((1,2-乙二基)双(亚硝酰丙二炔)]双酚}与牛的结合血清白蛋白(BSA)已被合成和表征。注意力集中在这种人工金属酶对H 2 O 2对多种硫化物的对映选择性氧化的催化活性上。。研究了pH,温度,催化剂和氧化剂浓度等参数对硫代苯甲醚的影响。在最佳条件下,BSA–CoL作为杂化生物催化剂可有效地对一系列硫化物进行对映选择性氧化,产生相应的亚砜,具有优异的转化率(最高100%),化学选择性(最高100%)和良好的对映体纯度(最高在某些情况下为87%ee)。
In Situ Generation of Unstable Difluoromethylphosphonate-Containing Diazoalkanes and Their Use in [3 + 2] Cycloaddition Reactions with Vinyl Sulfones
作者:Haibo Mei、Li Wang、Romana Pajkert、Qian Wang、Jingcheng Xu、Jiang Liu、Gerd-Volker Röschenthaler、Jianlin Han
DOI:10.1021/acs.orglett.1c00150
日期:2021.2.5
diazoalkanes with vinyl sulfones under simple reaction conditions is developed, which provides an efficient route toward functionalized fluorinated pyrazolines derivatives in good chemical yields. The difluoro diazoalkanes are generated in situ using t-BuONO for the diazotization of (β-amino-α,α-difluoroethyl)phosphonates, and their stabilities and reactivities were carefully investigated.
accessible sodiumformate as C1-source and K2S2O8 as reagent, a set of vinylsulfone substrates could be efficiently hydrocarboxylated in aqueous medium without any additional catalyst or reagent; and the concept could be also applied for direct hydroacylations, hydroalkylations and hydrophosphorylations. The control experiments clearly indicated that the reaction proceeds via radical mechanism without
我们报告了一种可见光介导的乙烯砜衍生物自由基加氢羧化方法。使用廉价易得的甲酸钠作为C1源,K 2 S 2 O 8作为试剂,一组乙烯基砜底物可以在水介质中有效地加氢羧化,无需任何额外的催化剂或试剂;该概念也可应用于直接加氢酰化、加氢烷基化和加氢磷酸化。对照实验清楚地表明该反应通过自由基机制进行,没有生成电子供体-受体(EDA)复合物;支持K 2 S 2 O 8原位引发的工作模型形成CO 2自由基阴离子。
Metal-free visible-light-promoted C(sp<sup>3</sup>)–H functionalization of aliphatic cyclic ethers using trace O<sub>2</sub>
作者:Ben Niu、Bryan G. Blackburn、Krishnakumar Sachidanandan、Maria Victoria Cooke、Sébastien Laulhé
DOI:10.1039/d1gc03482k
日期:——
Presented is a light-promoted C–C bond forming reaction yielding sulfone and phosphate derivatives at room temperature in the absence of metals or photoredox catalyst. This transformation proceeds in neat conditions through an auto-oxidationmechanism which is maintained through the leaching of trace amounts of O2 as sole green oxidant.