有机化学 ›› 2024, Vol. 44 ›› Issue (10): 3233-3240.DOI: 10.6023/cjoc202405049 上一篇    下一篇

研究论文

硼促进Co催化使用CO2和H2实现仲芳香胺N-甲基化

石亲a,b, 李臻a, 何林a,*(), 李玉东a,*(), 李跃辉c,*()   

  1. a 中国科学院兰州化学物理研究所 低碳催化与二氧化碳利用国家重点实验室(筹) 羰基合成与选择氧化国家重点实验室 兰州 730000
    b 中国科学院大学 北京 100049
    c 上海交通大学 国家电投智慧能源创新学院 上海 200240
  • 收稿日期:2024-05-31 修回日期:2024-07-16 发布日期:2024-08-16
  • 通讯作者: 何林, 李玉东, 李跃辉
  • 基金资助:
    国家自然科学基金(22022204); 国家自然科学基金(22102197); 江苏省国家自然基金(BK20211096); 江苏省国家自然基金(BK20211093)

Boron-Promoted Co-Catalyzed N-Methylation of Secondary Aromatic Amines with CO2 and H2

Qin Shia,b, Zhen Lia, Lin Hea(), Yudong Lia(), Yuehui Lic()   

  1. a State Key Laboratory of Low Carbon Catalysis and Carbon Dioxide Utilization; State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000
    b University of Chinese Academy of Sciences, Beijing 100049
    c College of Smart Energy, Shanghai Jiao Tong University, Shanghai 200240
  • Received:2024-05-31 Revised:2024-07-16 Published:2024-08-16
  • Contact: Lin He, Yudong Li, Yuehui Li
  • Supported by:
    National Natural Science Foundation of China(22022204); National Natural Science Foundation of China(22102197); National Science Foundation of Jiangsu Province(BK20211096); National Science Foundation of Jiangsu Province(BK20211093)

以CO2/H2为新型甲基化试剂, 对于发展绿色甲基化方法, 建立高效CO2利用新体系具有重要意义. 本工作基于硼活化甲酸根钴中间体策略, 以爪型三膦配体Triphos原位与Co形成催化剂, 实现了温和条件下的N—H甲基化反应. 该体系适用于芳香二级胺类底物, 并表现出优秀的化学选择性和官能团兼容性, 在60~80 ℃反应条件下, 对25个底物反应获得了38%~96%的收率. 基于对照实验结果推测, Lewis酸通过B—O相互作用活化甲酸钴物种, 接受胺分子的亲核进攻生成物种B, 之后脱水生成反应的关键中间体C.

关键词: 二氧化碳/氢气, N-甲基化反应, 钴催化

Development of catalytic methods using CO2/H2 as methylating reagent for selective methylation of amines is highly attractive. Herein, the methylation of N—H bond via boron promoted activation of Co-formate intermediates is reported. This catalytic system showed excellent functional group tolerance with high catalytic activity, and a series of methylated products were acquired in moderate to excellent yields under mild conditions (e.g. 80 ℃ or 60 ℃). It was inferred that imine complex C was the crucial intermediate formed via dehydration of species B, providing efficient C—N coupling for the selective N-methylation of secondary aromatic amines with CO2/H2.

Key words: CO2/H2, N-methylation, cobalt catalysis