The [3+2] Annulation of CF3-Ketimines by Re Catalysis: Access to CF3-Containing Amino Heterocycles and Polyamides

Saisai Zhang; Xun-Yong Liu; Zhenbang Chang; Xinxin Qiao; Heng-Ying Xiong; Guangwu Zhang

doi:10.1016/j.isci.2020.101705

The [3+2] Annulation of CF₃-Ketimines by Re Catalysis: Access to CF₃-Containing Amino Heterocycles and Polyamides

iScience. 2020 Oct 20;23(11):101705. doi: 10.1016/j.isci.2020.101705. eCollection 2020 Nov 20.

Authors

Saisai Zhang¹, Xun-Yong Liu², Zhenbang Chang¹, Xinxin Qiao¹, Heng-Ying Xiong¹, Guangwu Zhang¹

Affiliations

¹ Institute of Organic Functional Molecules, College of Chemistry and Chemical Engineering, Henan University, Kaifeng, 475004, P.R. China.
² School of Chemistry and Materials Science, Ludong University, Yantai, 264025, P.R. China.

Abstract

Transition metal catalyzed [3 + 2] annulation of imines with double bonds via directed C-H activation offers a direct access to amino cyclic motifs. However, owing to weak coordination and steric hindrance, trifluoromethylated ketimines have been an unaddressed challenge for TM-catalyzed annulations. Here, a rhenium-catalyzed [3 + 2] annulation of trifluoromethylated ketimines with isocyanates via C(sp²)-H activation has been disclosed. This approach provides an efficient platform for rapid access to a privileged library of CF₃-containing iminoisoindolinones and polyamides by utilizing challenging CF₃-ketimines as the annulation component. The capability of gram scale synthesis, the post-functionalization of the cyclization adduct, the derivation of complex natural molecules and the facile synthesis of polyamides highlight a diversity of synthetic potential of the current methodology.

Keywords: Catalysis; Chemistry; Molecular Inorganic Chemistry; Organic Synthesis.