Porphyrin-Based Conjugated Microporous Polymer Tubes: Template-Free Synthesis and A Photocatalyst for Visible-Light-Driven Thiocyanation of Anilines

Conjugated microporous polymers (CMPs) represent an important type of functional materials. In this area, morphological engineering has remained a major challenge. Here, we report the synthesis of porphyrin-based CMP tubes (CMP-1) through a template-free protocol. A mechanism study reveals that the CMP tubes are formed by the scrolling and closing of ribbon-like structures. The tubes possess a high specific surface area of 495 m2/g, along with improved optical properties including broadened absorption in the visible-light region, longer triplet-state lifetime, and more stable photocurrent, compared to those of the irregular solid CMP counterpart. When serving as a metal-free photocatalyst for an undocumented visible-light-driven thiocyanation of anilines, CMP-1 exhibits excellent photocatalytic performance, with single chemoselectivity and high yields for the conversion of 25 types of anilines at ambient conditions. This study fills in the gap of the tubular morphological engineering of CMPs and broadens the scope of their potential applications.