Synthetic Aspects of Metal‐Catalyzed Oxidations of Amines and Related Reactions

Abstract

The metabolism of amines is governed by a variety of enzymes such as amine oxidase, flavoenzyme, and cytochrome P‐450. A wide variety of compounds are produced such as ammonia and alkaloids in selective and clean oxidation reactions that proceed under mild reaction conditions. Simulation of the functions of these enzymes with simple transition metal complex catalysts may lead to the discovery of biomimetic, catalytic oxidations of amines and related compounds. Indeed, metal complex catalyzed oxidations have been found to proceed with high efficiency. The first section of this review discusses the dehydrogenative oxidations of amines with transition metal catalysts by transition metal catalysts that simulate amine oxidase. The second section highlights the catalytic oxidation of secondary amines to nitrones by simulation of flavoenzymes. The third section describes the simulation of the function of cytochrome P‐450 with lowvalent ruthenium complexes and peroxides. Biomimetic ruthenium‐catalyzed oxidations of tertiary amines, secondary amines, and other substrates such as amides, β‐lactams, nitriles, alcohols, alkenes, ketones, and even nonactivated hydrocarbons can be performed selectively under mild conditions. These three general approaches provide highly useful strategies for synthesis of fine chemicals and biologically active compounds such as alkaloids, amino acids, and β‐lactams.

Cu-catalyzed cross-dehydrogenative coupling: A versatile strategy for C–C bond formations via the oxidative activation of sp 3 C–H bonds

“…In an ionic mechanism (Scheme 10), copper catalyst is oxidized to oxy-copper 34 (80) by TBHP (81). The high Lewis-acidic copper species 34 coordinates to the nitrogen atom and forms a intermediate 35.…”

Oxidation of olefins catalyzed by new binaphthyl-ruthenium(III) complexes

“…Infrared (IR) spectra were recorded on a Shimadzu FT-IR-4100 spectrometer. 1 H and 13 C NMR spectra were measured on a JEOL JNM GSX-270 using CDCl 3…”

Beyond Traditional Cross Couplings: The Scope of the Cross Dehydrogenative Coupling Reaction

“…[28][29][30][31] Initially it is assumed that there is activation of the carbon a-to the amine through the formation of an iminium ion coordinated to the copper catalyst, the formation of this species is envisaged to be facilitated by the presence of the copper and the oxidant. By oxidative a-CÀH activation of the amine, a "free-radical" species could be generated and through a single electron transfer (SET) with the copper to generate the copper iminium species.…”