Functions of Phytic Acid in Fabricating Metal-Free Carbocatalyst for Oxidative Coupling of Benzylamines†

Summary of main observation and conclusion Sustainable phytic acid and cellulose are selected as precursors to fabricate P-doped carbon material (C-P-500), which possesses the high surface area and exhibits excellent catalytic activity and stability in the oxidative coupling of benzylamines (conversion > 95%, yield > 95%). During the carbonization of cellulose in the muffle furnace, phytic acid can efficiently prevent the cellulose-derived carbon from combustion and create micro/meso porous structure because of its special function of fire retardation. Control experiments and characterizations demonstrate that P-containing groups anchoring on C-P-500 improve the catalytic performance of carbocatalyst in the oxidation of benzylamines to imines. The excellent catalytic activity of C-P-500 should be contributed collectively by carbonyl and P=O(OH) 2 groups. Due to the sustainable property of precursors and simple methodology for fabricating P-doped carbocatalyst, along with the moderate reaction conditions, it is a green catalytic system for the oxidative coupling of benzylamines to imines.