A β-ketoenamine-linked covalent organic framework as a heterogeneous photocatalyst for the synthesis of 2-arylbenzothiazoles by cyclization reaction

Abstract

Visible light-mediated catalysis has gradually become an important means of green catalytic organic synthesis. However, traditional photosensitizers (organic dyes or precious transition metal complexes, for instance) have limited applications due to their inherent toxicity and non-reusability. A β-ketoenamine-linked covalent organic framework (TAPT-TP-COF), as a heterogeneous photocatalyst, was synthesized by solvothermal reaction and characterized by FT-IR, XPS, SEM, TEM, XRD, BET and optical performance tests. The TAPT-TP-COF exhibited favorable photocatalytic activity, remarkable substrate scope and recyclability performance for the synthesis of 2-arylbenzothiazoles by the intramolecular cyclization reaction of N-arylbenzothioamides. This research provides a new solution for the cyclization reaction in the field of photocatalysis.