Interfacial Frustrated Lewis Pairs of CeO<sub>2</sub> Activate CO<sub>2</sub> for Selective Tandem Transformation of Olefins and CO<sub>2</sub> into Cyclic Carbonates
Herein, defect-enriched CeO2 with constructed interfacial frustratedLewispairs (FLPs, two adjacent Ce3+…O2-, Figure 1) effectively activates CO2 via the interactions between C/Lewis basic lattice O2- and the two O atoms in CO2/two adjacent Lewisacidic Ce3+ ions. Selective cyclic carbonate production from a catalytically tandem protocol of olefins and CO2 is used to demonstrate FLP-inspired CO2 activation
CO2 的有效活化是在有机合成中有效利用 CO2 的先决条件。精确控制固体的界面事件显示出激活的潜力。在此,缺陷富集的 CeO2 与构造的界面受挫路易斯对(FLP,两个相邻的 Ce3+…O2-,图 1)通过 C/Lewis 基本晶格 O2- 和 CO2/两个相邻路易斯中的两个 O 原子之间的相互作用有效地激活了 CO2酸性 Ce3+ 离子。从烯烃和 CO2 的催化串联协议中选择性生产环状碳酸酯用于证明 FLP 启发的 CO2 活化。
An in situ formed Ca<sup>2+</sup>–crown ether complex and its use in CO<sub>2</sub>-fixation reactions with terminal and internal epoxides
作者:J. Steinbauer、A. Spannenberg、T. Werner
DOI:10.1039/c7gc01114h
日期:——
Calcium punched beyond its weight: An in situ formed Ca2+–crown ether complex showed unprecedented efficiency in cyclic carbonate synthesis.
钙超出了其重量范围:一种原位形成的Ca2+–冠醚复合物在环状碳酸酯合成中表现出前所未有的效率。
Efficient Catalytic System Involving Molybdenyl Acetylacetonate and Immobilized Tributylammonium Chloride for the Direct Synthesis of Cyclic Carbonates from Carbon Dioxide and Olefins
An effective direct method for preparing of cyclic carbonates from CO2 and olefins in the presence of tert-butyl hydroperoxide as an oxidant was provided. The first stage, the epoxidation of olefins, was carried out using MoO2(acac)2 as a catalyst (1h, 100 °C), and the second stage, the cycloaddition of CO2 to the resulting epoxide, was proceeded in the presence of immobilized tributylmethylammonium
Electrogenerated bases promote the reaction between primary alcohols and carbondioxide to give organic carbonates in excellent yields. Secondary alcohols are converted in moderate yields, whereas tertiary alcohols and phenols are unreactive. 1,2-Diols give a mixture of both cyclic and linear di- and monocarbonates. These latter are intermediates in the reaction pathway leading to the cyclic derivatives
Diphenyl Carbonate: A Highly Reactive and Green Carbonyl Source for the Synthesis of Cyclic Carbonates
作者:Ek Raj Baral、Jun Hee Lee、Jeung Gon Kim
DOI:10.1021/acs.joc.8b01695
日期:2018.10.5
A practical, safe, and highly efficient carbonylation system involving a diphenylcarbonate, an organocatalyst, and various diols is presented herein and produces highly valuable cyclic carbonates. In reactions with a wide range of diols, diphenylcarbonate was activated by bicyclic guanidine 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) as a catalyst, which successfully replaced highly toxic and unstable