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

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(sp ² )-H activation has been disclosed. This approach provides an efficient platform for rapid access to a privileged library of CF ₃ -containing iminoisoindolinones and polyamides by utilizing challenging CF ₃ -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.
Competing Interests: The authors declare no competing financial interests.
(© 2020 The Author(s).)