Selective Ruthenium-Catalyzed Transformation of Carbon Dioxide: An Alternative Approach toward Formaldehyde
作者:Max Siebert、Max Seibicke、Alexander F. Siegle、Sabrina Kräh、Oliver Trapp
DOI:10.1021/jacs.8b10233
日期:2019.1.9
one-step synthesis of a formaldehyde derivative starting fromcarbon dioxide and hydrogen gas utilizing a homogeneous ruthenium catalyst. Here, formaldehyde is obtained as dimethoxymethane, its dimethyl acetal, by selective reduction of carbon dioxide at moderate temperatures (90 °C) and partial pressures (90 bar H2/20 bar CO2) in the presence of methanol. Besides the desired product, only methyl formate
甲醛是许多工业过程的重要前体,每年在能量不利和原子效率低的工业过程中通过甲醇催化氧化产生数百万吨的规模。在这项工作中,我们提出了一种使用均相钌催化剂从二氧化碳和氢气开始的甲醛衍生物的高选择性一步合成。在这里,甲醛是通过在中等温度 (90 °C) 和分压 (90 bar H2/20 bar CO2) 下在甲醇存在下选择性还原二氧化碳而获得的二甲氧基甲烷,即其二甲基缩醛。除了所需的产物外,仅形成甲酸甲酯,可在连续的催化步骤中将其转化为二甲氧基甲烷。通过对催化体系的综合筛选,
Access to 3‐Azetidines via Halogenation of Titanacyclobutanes
作者:Tyler D. Weinhold、James A. Law、James H. Frederich
DOI:10.1002/adsc.202301527
日期:——
Azetidines are valuable nitrogenous heterocycles. Herein, we disclose a strategy for the modular assembly of 3‐azetidines and related spirocyclic congeners featuring all‐carbon quaternary centers. This approach leverages titanacyclobutanes generated from ketones or alkenes. Halogenation of these organotitanium species gives rise to functionalized alkyl dihalides that can be subsequently captured by
Novel quasi-scorpionate ligand structures based on a bis-N-heterocyclic carbene chelate core: synthesis, complexation and catalysis
作者:Sedat Yasar、Kingsley J. Cavell、Benjamin D. Ward、Benson Kariuki
DOI:10.1002/aoc.1773
日期:2011.5
pyridyl donor, were prepared. The coordinationchemistry of these ligands was investigated with silver, palladium, rhodium and iridium. The single crystal X‐ray structures of [Rh(NC2Me)(COD)]Cl 8a and [Ir(NC2Pr)(COD)]Br 9b were determined. The catalytic potential of the rhodium and iridiumcomplexes was assessed in the transfer hydrogenation of ketones; the iridiumcomplexes, which show superior performance