Guo Shuoshuo, Wu Yongmeng, Wang Changhong, Gao Ying, Li Mengyang, Zhang Bin, Liu Cuibo
Department of Chemistry, School of Science, Institute of Molecular Plus, Tianjin University, 300072, Tianjin, China.
Green Catalysis Center, College of Chemistry, Zhengzhou University, 450000, Zhengzhou, China.
Nat Commun. 2022 Sep 8;13(1):5297. doi: 10.1038/s41467-022-32933-6.
Room temperature and selective hydrogenation of quinolines to 1,2,3,4-tetrahydroquinolines using a safe and clean hydrogen donor catalyzed by cost-effective materials is significant yet challenging because of the difficult activation of quinolines and H. Here, a fluorine-modified cobalt catalyst is synthesized via electroreduction of a Co(OH)F precursor that exhibits high activity for electrocatalytic hydrogenation of quinolines by using HO as the hydrogen source to produce 1,2,3,4-tetrahydroquinolines with up to 99% selectivity and 94% isolated yield under ambient conditions. Fluorine surface-sites are shown to enhance the adsorption of quinolines and promote water activation to produce active atomic hydrogen (H*) by forming F-K(HO) networks. A 1,4/2,3-addition pathway involving H* is proposed through combining experimental and theoretical results. Wide substrate scopes, scalable synthesis of bioactive precursors, facile preparation of deuterated analogues, and the paired synthesis of 1,2,3,4-tetrahydroquinoline and industrially important adiponitrile at a low voltage highlight the promising applications of this methodology.
使用具有成本效益的材料催化，以安全清洁的氢供体将喹啉室温选择性氢化为1,2,3,4-四氢喹啉具有重要意义，但由于喹啉和氢的活化困难，这一过程具有挑战性。在此，通过对Co(OH)F前驱体进行电还原合成了一种氟改性钴催化剂，该催化剂以水为氢源，对喹啉的电催化氢化表现出高活性，在环境条件下可选择性高达99%、分离产率达94%地制备1,2,3,4-四氢喹啉。研究表明，氟表面位点可增强喹啉的吸附，并通过形成F-K(HO)网络促进水活化以产生活性原子氢（H*）。结合实验和理论结果，提出了一条涉及H*的1,4/2,3-加成途径。该方法具有广泛的底物范围、可扩展合成生物活性前体、易于制备氘代类似物以及在低电压下成对合成1,2,3,4-四氢喹啉和工业上重要的己二腈等优点，突出了其应用前景。
