苝二酰亚胺共价有机框架超级还原剂用于高效光催化芳基卤化物还原反应  

Perylene diimide covalent organic frameworks super-reductant for visible light-driven reduction of aryl halides

作　　者：金昱丞 刘小琳[1] 曲琛 李长骏 王海龙[1] 詹晓宁 曹昕怡 李晓锋 于宝秋 张琪[1] 齐冬冬 姜建壮[1] Yucheng Jin;Xiaolin Liu;Chen Qu;Changjun Li;Hailong Wang;Xiaoning Zhan;Xinyi Cao;Xiaofeng Li;Baoqiu Yu;Qi Zhang;Dongdong Qi;Jianzhuang Jiang(Beijing Advanced Innovation Center for Materials Genome Engineering,Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline Materials,Department of Chemistry,University of Science and Technology Beijing,Beijing 100083,China;State Key Laboratory of Organic‐Inorganic Composites,College of Materials Science and Engineering,Beijing University of Chemical Technology,Beijing 100029,China)

机构地区：[1]北京科技大学化学系,功能分子与晶态材料科学与应用北京市重点实验室,北京材料基因组工程高级创新中心,北京100083 [2]北京化工大学材料科学与工程学院,有机-无机复合材料国家重点实验室,北京100029

出　　处：《Chinese Journal of Catalysis》2024年第2期171-183,共13页催化学报（英文）

基　　金：国家自然科学基金(22235001,22175020,22131005,22261132512);小米青年学者计划;中央高校基本科研业务费(FRF-EYIT-23-02);北京科技大学.

摘　　要：自由基离子型分子光催化剂被证实是具有很强还原能力的可见光超级还原剂,它们在促进惰性的有机反应(例如将芳基卤化物还原为芳基自由基)方面具有突出的催化能力.然而,由于分子聚集严重地降低其催化活性,因而针对非均相超级还原剂的研究较少.本文提出了一种新的方法来解决上述问题,通过溶剂热反应将具有连续光诱导电子转移机制的苝二亚胺超级还原剂(PDI)异质化为二维给体-受体(D-A)共价有机框架(COFs).即以N,N'-双(3-戊基)-2,5,8,11-四(4-甲酰基苯基)苝二酰亚胺(TFPDI)与1,3,6,8-四(4-氨基苯基)芘\(Py-TA)或2,3,6,7-四(4-氨基基苯基)四硫富瓦烯(TTF-TA)为原料,通过溶剂热反应分别制备了两种高晶态二维D-A型COF结构:USTB-21和USTB-22,并用于芳基氯化物、芳基溴化物和芳基碘化物的光催化还原反应.X射线衍射和理论模拟结果表明,USTB-21和USTB-22具有二维共价键连接的层状结构,分别呈现AA和AB的堆积方式.在各自最佳反应条件下,COFs显示出与均相催化剂相媲美的可见光催化性能,可高效地还原一系列芳基氯化物、芳基溴化物和芳基碘化物.其中,USTB-22在可见光驱动不同的芳香卤化物还原时,3 h内的转化率高达99%.瞬态吸收光谱结果表明,相比于均相催化剂(N,N'-双(2,6-二异丙基苯基)苝二酰亚胺),自由基阴离子激发态寿命是150 ps,USTB-21和USTB-22具有更长的激发态寿命,分别为210和260 ps.顺磁共振波谱测试结果证明,自由基阴离子光催化剂异质化成晶态D-A型COFs能够有效地促进电荷分离效率和延长激发态寿命.上述结果说明,USTB-22具有良好的光催化性能主要是因为其激发态寿命较长以及电荷分离效率较好.理论模拟结果表明,所制备的材料具有D-A型的电子结构.对COF的模型片段进行理论计算,揭示了各步反应路径中吉布斯自由能的变化,从而进一步阐明了光催化机理.在催化反应过程中,芳In recent years,there has been a growing interest in the utilization of molecular photocatalysts in their radical ionic forms,especially as visible-light super-reductants.These catalysts exhibit remarkable capabilities in facilitating otherwise inert high-potential organic reactions,such as the reduction of aryl halides to aryl radicals.However,the development of heterogeneous super-reductants has lagged behind due to the deactivation effect caused by molecular aggregation.This study presents a novel approach to address this limitation by heterogenizing perylene diimides(PDIs)super-reductants with a consecutive photo-induced electron transfer mechanism into two-dimensional donor-acceptor(D-A)covalent organic frameworks(COFs).Both COFs,possessing D-A electronic structures and photothermal effects,demonstrated superior visible-light photocatalytic performance compared to their homogeneous counterparts.They achieved up to 99%conversion in the dehalogenation of aryl halides,primarily through a hydrogen atom trapping aryl radical mechanism.Additionally,we conducted a comparative investigation of the excited states of radical anionic D-A-type COFs and DPPDI using femtosecond transient absorption spectroscopy.Notably,the lifetimes of COFs were significantly prolonged,measuring 210 and 260 ps,respectively,compared to the 150 ps lifetime of(DPPDI•−).This study offers valuable insights into the design of efficient free radical ion-type photocatalysts,with potential applications in various chemical transformations.

关 键 词：苝酰亚胺 共价有机骨架 光催化剂 均相 芳基卤化物的还原 

分 类 号：O643.3[理学—物理化学]