Azide promotion of alkane oxidations catalyzed by metal complexes in solution

The oxidation of light alkanes catalyzed by metal complexes in solution is promoted by Group 1 metal azides. Yields of oxygenated reaction products are greatly enhanced when catalytic amounts of azides are added to the reaction mixture. The addition of sodium azide to oxidations catalyzed by transition metal acetylacetonates, heteropolyacids, polyoxometallates, phthalocyanines, bis-(pyridylimino)isoindolines, porphyrins and Schiff bases significantly enhances rates of low-temperature catalytic oxidation reactions in the liquid phase. Earlier work showed that Cr(III), Mn(III), Fe(III) and Co(III) complexes of electron-deficient macrocyclic complexes exhibited remarkable catalytic activity for oxidizing light alkanes. Such complexes bearing axial azide ligands were far more active than their axial chloride or acelate counterparts.