A Recyclable Triangular Phenanthrenequinone (TPQ) Catalyst-in-a-Teabag System for Biomimetic Aerobic Oxidation of Benzylamines

An insoluble triangular phenanthrenequinone (TPQ) catalyst was developed and applied in a reusable "catalyst-in-a-teabag" system for the aerobic oxidation of benzylamines. Encapsulation of TPQ in a permeable PTFE pouch enabled efficient aerobic oxidation under mild conditions, affording imine products in excellent yields and easy catalyst recovery. The TPQ catalyst exhibited high reusability with full activity restoration after acid-alcohol reactivation, providing a practical and sustainable approach to biomimetic aerobic oxidation.