有机化学 ›› 2023, Vol. 43 ›› Issue (8): 2848-2854.DOI: 10.6023/cjoc202210018 上一篇    下一篇

研究论文

光促进双(4-二苯甲酮)苯醚催化C(sp3)—H键活化构建C—S键

王灵娜a, 刘晓庆a, 林钢a, 金泓颖a, 焦民均a, 刘雪粉b, 罗书平a,*()   

  1. a 浙江工业大学 绿色化学合成技术国家重点实验室培育基地 杭州 310014
    b 杭州师范大学工学院 杭州 310014
  • 收稿日期:2022-10-18 修回日期:2023-01-09 发布日期:2023-04-21
  • 基金资助:
    国家自然科学基金(21376222); 浙江省自然科学基金(LY18B060011)

Photocatalytic Activation of C(sp3)—H Bonds to Form C—S Bonds Catalyzed by (Oxybis(4,1-phenylene))bis(phenylmethanone)

Lingna Wanga, Xiaoqing Liua, Gang Lina, Hongying Jina, Minjun Jiaoa, Xuefen Liub, Shuping Luoa()   

  1. a State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Zhejiang University of Technology, Hangzhou 310014
    b Institute of Technology, Hangzhou Normal University, Hangzhou 310014
  • Received:2022-10-18 Revised:2023-01-09 Published:2023-04-21
  • Contact: *E-mail: luoshuping@zjut.edu.cn
  • Supported by:
    The National Natural Science Foundation(21376222); The Natural Science Foundation of Zhejiang Province(LY18B060011)

以二芳基二硫醚为硫源, 实现了光催化甲苯及其衍生物的C(sp3)—H键活化, 以45%~93%的收率得到了一系列硫醚化合物. 其中, 新型氢原子转移(HAT)光敏剂双(4-二苯甲酮)苯醚表现出优异的光转化效率, 最高达到9.3×10-1 mmol•kW-1•h-1. 与二苯甲酮(1.7×10-1 mmol•kW-1•h-1)相比, 光转化效率提高了5倍. 此外通过对反应机理进行研究, 提出了该光催化反应的可能机理: 二苯甲酮类似物作为光敏剂可以在三线激发态攫取甲苯甲基上的氢原子, 得到苄基自由基, 然后与二芳基二硫醚经光照均裂得到的硫自由基进行成键反应得到硫醚化合物, 同时另一部分硫自由基在碱的辅助下, 通过单电子氧化二苯甲醇类自由基回到二苯甲酮基态, 完成光催化循环.

关键词: 光催化, 有机光敏剂, C(sp3)—H键活化, 硫醚化

The photocatalytic C(sp3)—H bond activated thioetherification of toluene and its derivatives was carried out with diaryl disulfide as sulfur source, and a series of thioether compounds with 45%~93% yields. Among them, the catalysis of new hydrogen atom transfer (HAT) photosensitizer of (oxybis(4,1-phenylene))bis(phenylmethanone) showed excellent light conversion efficiency, up to 9.3×10-1 mmol•kW-1•h-1. Compared with benzophenone (1.7×10-1 mmol•kW-1•h-1), the light conversion efficiency was 5 times higher. In addition, through the study of the reaction mechanism, the possible mechanism of the benzophenone analogs in the three-line excited state grab hydrogen atoms of toluene methyl to obtain benzyl radicals, then diphenyl sulfide is homolytically cleaved by LEDs irradiation to obtain sulfur radicals, and the bond formation reaction is carried out to obtain sulfide compounds. At the same time, another part of the sulfur radicals under alkali auxiliary through single electron oxidation of benzyl alcohol free radicals returns to the state of benzophenone, completing the photocatalytic cycle.

Key words: photocatalysis, organic photosensitizer, C(sp3)—H bond activation, thioetherification