过渡金属催化CO_(2)氢化反应研究进展

Advances on Transition-Metal Catalyzed CO_(2) Hydrogenation

二氧化碳(CO_(2))是主要的温室气体,由于人类过度使用化石资源导致大气中CO_(2)浓度增加,进而引发全球环境问题.另一方面,CO_(2)是一种理想的C1资源,具有安全、储量丰富和廉价易得等优点.因此如何将CO_(2)应用于有机合成以获得化工产品与燃料,已成为当前研究热点.其中,过渡金属催化的CO_(2)氢化反应是CO_(2)资源化利用的重要途径,反应可以在温和条件下选择性地生成2e、4e和6e还原产物,如甲酸、甲酰胺、甲酸酯、甲醛、甲醇以及C2+醇等产物,具有广阔的应用前景,因此引人注目.系统总结了近来过渡金属配合物催化CO_(2)加氢反应的研究进展,主要对催化剂的种类和结构、活性及其产物选择性等进行总结,并对近来所发展的与CCU(CO_(2) capture and utilization)策略相关的CO_(2)原位催化氢化反应进行了分析与讨论.此外,对本领域中存在的挑战及展望进行了分析.

Carbon dioxide(CO_(2))is the main greenhouse gas,the excessive burning of fossil fuels leads to the increasing of CO_(2) concentration,resulting in global warming.On the other hand,CO_(2) is regarded as an ideal C1 source due to its nontoxicity,abundance and availability.Hence,the transformation of CO_(2) into fine chemicals and hydrocarbon fuels in organic synthesis is becoming one of hot research fields.Among them,the transition-metal catalyzed CO_(2) hydrogenation is an appealing and promising approach for CO_(2) utilization with wide potential applications,thus leading to selective fromation of 2e,4e,and 6e reductive products including formic acid,formamide,formate,formaldehyde,methanol and C2+alcohols under mild reaction conditions.In this review,the recent advances on transition metal complexe-catalyzed CO_(2) hydrogenation are in detail summarized on the basis of the molecular structures,activities of the homogeneous catalysts,and product selectivity controlling.This review also gives an overview on the in situ catalytic hydrogenation corresponding to the recently developed CCU(CO_(2) capture and utilization)strategy.Furthermore,the challenges and perspectives in homogeneous catalytic hydrogenation field are also given in this article.