Versatile and scalable synthesis of cyclic organic carbonates under organocatalytic continuous flow conditions
作者:Romaric Gérardy、Julien Estager、Patricia Luis、Damien P. Debecker、Jean-Christophe M. Monbaliu
DOI:10.1039/c9cy01659g
日期:——
epoxides. In this work, cyclic organic carbonates are prepared according to alternative sustainable and intensified continuousflow conditions from the corresponding 1,2-diols. The process utilizes dimethyl carbonate (DMC) as a low toxicity carbonation reagent and relies on the organocatalytic activity of widely available and cheap organic ammonium and phosphonium salts. Glycerol is selected as a model
Fast Addition of s‐Block Organometallic Reagents to CO
<sub>2</sub>
‐Derived Cyclic Carbonates at Room Temperature, Under Air, and in 2‐Methyltetrahydrofuran
作者:David Elorriaga、Felipe Cruz‐Martínez、María Jesús Rodríguez‐Álvarez、Agustín Lara‐Sánchez、José Antonio Castro‐Osma、Joaquín García‐Álvarez
DOI:10.1002/cssc.202100262
日期:2021.5.6
straightforward synthesis of: highly substituted tertiary alcohols, β‐hydroxy esters, or symmetric ketones, working always under air and at room temperature. Finally, an unprecedented one‐pot/two‐step hybrid protocol is developed through combination of an Al‐catalyzed cycloaddition of CO2 and propylene oxide with the concomitant fast addition of RLi reagents to the in situ and transiently formed cyclic carbonate
Highly regio- and stereoselective synthesis of cyclic carbonates from biomass-derived polyols<i>via</i>organocatalytic cascade reaction
作者:Hui Zhou、Hui Zhang、Sen Mu、Wen-Zhen Zhang、Wei-Min Ren、Xiao-Bing Lu
DOI:10.1039/c9gc03013a
日期:——
The cascade reaction of CO2, vicinal diols, and propargylicalcohol, was firstly achieved by dual Lewis base (LB) organocatalytic systems involving LB–CO2 adducts and commercially available organic amines. This methodology could overcome the chemical inertness of CO2, providing an alternative route to various functionalized five-membered cyclic carbonates in moderate to high yields under mild reaction
CO 2,邻二醇和炔丙醇的级联反应首先通过双路易斯碱(LB)有机催化体系实现,该体系涉及LB–CO 2加合物和可商购的有机胺。该方法可以克服CO 2的化学惰性,在温和的反应条件下(25°C,1.0 atm CO 2)以中等至高收率提供各种功能化的五元环状碳酸酯的替代路线)。更重要的是,该方法还可以用于由生物质衍生的多元醇轻松有效地合成手性多环碳酸酯,并完全保留手性中心的构型。这项研究为构建具有多功能基团和手性中心的增值环状碳酸酯提供了一种环境友好,可扩展且具有成本效益的方案。
Activation of (salen)CoI complex by phosphorane for carbon dioxide transformation at ambient temperature and pressure
the reaction of carbon dioxide with terminal epoxides or aziridines at ambient temperature and 1 bar carbon dioxide pressure. Only 1.0 mol% of both (salen)CoI 3g and phosphorane 4d are required for cyclic carbonate synthesis, and the catalyst loading could even be lowered down to 0.1 mol%. Under this condition, no polycarbonate formation is detected by NMR analysis. It is proposed that the high efficiency