Magnetic N-containing carbon spheres derived from sustainable chitin for the selective oxidation of C–H bonds

A kind of magnetic N-containing carbon material was synthesized by a simple method using sustainable N-acetyl-D-glucosamine (NAG) and iron nitrate as the raw materials. In C–H oxidation reactions such as the epoxidation of stilbene and styrene, and the oxidation of ethylbenzene, the carbon catalyst exhibited excellent catalytic activity and selectivity for the target products. The superparamagnetic properties at room temperature facilitated catalyst recycling and reusability when it was used as a catalyst. The relationship between the catalytic results and the N 1s XPS analysis indicated that the graphitic N species located in the carbon skeleton was the key accelerating factor which promoted the catalytic C–H oxidation. Density functional theory (DFT) calculations further indicated that the iron species were not an essential factor but they acted as promoters for the catalytic performance of the catalyst. This study will expand the application of biomass-based heteroatom-containing compounds.