Enzymatic Oxidation of —CH₃ to —CHO

Abstract

WE have previously shown¹ that peroxidase, together with hydrogen peroxide, will oxidize mesidine (I) to the purple crystalline compound 2 : 6-dimethylbenzoquinone-4-(2′ : 4′ : 6′-trimethyl) anil (V) in 95 per cent yield. When ferrous iron was substituted for the enzyme, the product was mainly ill-defined amorphous material. This enzymatic oxidation involves the elimination of a methyl group, and at the time we postulated the intermediate formation of 2 : 6-dimethylbenzoquinone (II) to explain the reaction. More recently we have shown² that the peroxidase system will oxidize 4-methoxy-2 : 6-di-methylaniline with the facile elimination of a methoxyl group (detected as methyl alcohol). p-Anisidine is also oxidized³, with the elimination of a methoxyl group, to 2-amino-5-p-anisidinobenzoquinone-bis-anisylimine and tetra-p-methoxy azophenine.