637-44-5Relevant articles and documents
Bulky 1,1′-bisphosphanoferrocenes and their coordination behaviour towards Cu(i)
Bruhn, Clemens,Buzsáki, Daniel,Dey, Subhayan,Kelemen, Zsolt,Pietschnig, Rudolf
, p. 6668 - 6681 (2020)
Two bulky mesityl substituted dppf-analogues Fe(C5H4PMes2)2 (Mes = 2,4,6-Me3C6H2, 1) and Fe(C5H4PMes2)(C5H4PPh2) (Mes = 2,4,6-Me3C6H2, Ph = C6H5, 3) have been prepared and their properties as donor ligands have been explored using heteronuclear NMR spectroscopy and in particular via1JP-Se coupling, cyclic voltammetry and DFT calculations. Based on the results obtained, a series of mono- and dinuclear Cu(i) complexes have been prepared with these new diphosphane ligands using Br-, I-, and BF4- as counter anions. For the very bulky ligand 1 rare and unprecedented double bridging complexation modes have been observed containing two non-planar Cu2Br2 units, while for the other dinuclear complexes planar Cu2Br2 units have been found. The Cu(i) complexes of 1 and 3 were then used as catalysts for CO2-fixation reaction with terminal alkynes, and complexes with ligand 3 were found to be more efficient than those with 1. DFT calculations performed on compounds 1, 3 and their Cu(i) complexes were able to verify the trend of these catalytic reactions.
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Coles,Hart
, p. 279 (1971)
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Method for synthesizing acetylenic acid by using terminal alkyne and carbon dioxide
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Paragraph 0052-0056; 0055-0057; 0058-0060; 0061-0063; ..., (2021/07/24)
The invention belongs to the field of organic synthesis, and particularly relates to a method for synthesizing acetylenic acid by using terminal alkyne and carbon dioxide. The method comprises the experimental steps that alkyne, alkali and a solvent are added into a reaction tube, the alkyne serves as a raw material, the alkali and the solvent provide a strong alkaline environment, CO2 is introduced into a reaction container to form a carbon dioxide atmosphere, heating and stirring reaction are carried out, after the reaction is finished, cooling is carried out to the room temperature, extraction and liquid separation are carried out, a water layer is acidified, then separation and purification are further carried out, and the acetylenic acid compound is obtained. The method is carried out under the conditions of low temperature and normal pressure, does not need to add a metal catalyst, is single in product and convenient to separate, good in substrate applicability and safe and simple to operate, and has potential industrial application prospects and good economic benefits.
Copper(I)-modified covalent organic framework for CO2 insertion to terminal alkynes
Bu, Ran,Zhang, Lin,Gao, Lu-Lu,Sun, Weng-Jie,Yang, Shuai-Liang,Gao, En-Qing
, (2020/12/21)
The carboxylation of terminal alkynes with CO2 is an attractive route for CO2 fixation and conversion, and various homogeneous Cu(I) catalysts have been explored for the reaction. However, it is still a challenge to develop efficient heterogeneous catalysts for the conversion under mild conditions. Considering that covalent organic frameworks (COFs) are emerging as versatile platforms for the design of functional materials, we developed a TpBpy-supported Cu(I) catalyst, where TpBpy is a stable imine-type porous COF furnished with rich N,N- and N,O-chelating sites for Cu(I) immobilization. The hybrid material can efficiently catalyze the conversion of CO2 and terminal alkynes to propiolic acids under relatively mild conditions (1 atm CO2, 60 ℃). The catalytic activity arises from the synergy between the organic framework of TpBpy and the Cu(I) sites. Not merely serving as a porous support to afford isolated and accessible Cu(I) sites, the organic framework itself has its own catalytic activity through the polar and basic N and O functional sites, which could activate the C–H bond and facilitate CO2 absorption. In addition, the framework also serves as a giant ligand to shift the reversible Cu(I)-catalyzed process in favor of carboxylation. The catalyst shows somewhat reduced activity after reused for three cycles owing to the oxidation of Cu(I) to Cu(II), but it can be easily regenerated by treating with KI.
N-Heterocyclic carbene-nitrogen molybdenum catalysts for utilization of CO2
Chen, Fei,Tao, Sheng,Liu, Ning,Dai, Bin
, (2021/01/19)
Three new N-heterocyclic carbene-nitrogen molybdenum complex was synthesized, and its catalytic activity was evaluated in the cycloaddition of epoxides with CO2. The molybdenum complex combined with tetrabutyl ammonium iodide (TBAI) resulted in a catalytic system for efficient conversion of a wide range of terminal and internal epoxides under 80 °C and 5–7 bar pressure for CO2. The cooperative catalysis mechanism between molybdenum complex and TBAI was elucidated, in which molybdenum complex was used as Lewis acid, and TBAI was employed as nucleophilic reagent. In addition, the NHC-Mo catalytic system was also successfully applied for the direct carboxylation of terminal alkynes with CO2.