【摘 要】
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A series of Bi(Ⅲ) porphyrin complexes were synthesized and tested as catalysts for chemical fixation of carbon dioxide (CO2) and epoxides under solvent-free conditions in the presence of tetrabutylamm
【机 构】
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The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, Colle
【出 处】
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中国化学会第十三届全国有机合成化学学术研讨会
论文部分内容阅读
A series of Bi(Ⅲ) porphyrin complexes were synthesized and tested as catalysts for chemical fixation of carbon dioxide (CO2) and epoxides under solvent-free conditions in the presence of tetrabutylammonium iodide (TBAI) as co-catalyst.The influences of various factors (catalyst systems,catalyst amount,pressure,time,and temperature) on the catalytic activities have been studied systemically.A 92.9% yield and >99% selectivity for propylene carbonate (PC) were obtained with 2a/TBAI as catalyst system under the optimized conditions (90 ℃,1 h,2 MPa).Notably,a very high turnover frequency (TOF) value (37900 h-1) for catalyst 2a was achieved via adjusting reactin factors.This binary catalytic system also exhibited good activities (up to 98%) and selectivities (>99%) for the cycloaddition reaction of a large scope of epoxides with CO2 into corresponding cyclic carbonates at atmospheric pressure within 6 h.In spite of the homogeneous property of this catalytic system,2a/TBAI could maintain the performance under atmospheric pressure for 60 h,or even more.Moreover,a plausible mechanism was given on the basis of the kinetic studies.
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