Recyclable anhydride catalyst for HO oxidation: -oxidation of pyridine derivatives.

The catalytic efficiency and recyclability of poly(maleic anhydride--1-octadecene) (Od-MA) and poly(maleic anhydride--1-isobutylene) (Bu-MA) were evaluated for use in the development of a metal-free, reusable catalyst for the oxidation of pyridines to pyridine -oxides in the presence of HO. The Od-MA catalyst was easily recovered filtration with recovery yields exceeding 99.8%. The catalyst retained its activity after multiple uses and did not require any treatment for reuse. The Od-MA and HO catalytic system described herein is eco-friendly, operationally simple, and cost-effective; thus, it is industrially applicable. Od-MA and HO could potentially be used in place of percarboxylic acid as an oxidant in a wide range of oxidation reactions.