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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.

RuCl3-catalyzed oxidative cyanation of tertiary amines with sodium cyanide under molecular oxygen (1 atm) at 60 degrees C gives the corresponding alpha-aminonitriles, which are versatile synthetic intermediates of various compounds such as amino acids and unsymmetrical 1,2-diamines, in excellent yields. This reaction is clean and should be an environmentally benign and useful process.

The sodium tungstate catalyzed oxidation of secondary amines with hydrogen peroxide gives the corresponding nitrones. Acyclic and cyclic nitrones can be obtained from secondary amines in a single step in good to excellent yields. The oxidation of secondary amines in the presence of alkenes gives isoxazolidines by 1,3-dipolar cycloaddition of nitrones. Introduction of a substituent at the «-position of secondary amines can be performed upon oxidation of secondary amines and subsequent treatment with various nucleophiles.

Primary alcohols undergo oxidative condensation upon treatment with RuH2(PPh3)4 catalyst to give esters and molecular hydrogen. Similarly, 1,4-and 1,5-diols can be converted into the corresponding 7-and -lactones, respectively. The lactonization is greatly enhanced by accepting hydrogen with an appropriate hydrogen acceptor such as acetone. Primary alcohols are oxidized chemoselectively in the presence of secondary alcohols to give

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Nitrones are important compounds and are highly useful in many aspects. The first part describes the methods for synthesis of nitrones, which are useful and environmentally friendly. Catalytic oxidations, condensations, and other useful reactions are described. The nitrones thus obtained are key intermediates for the synthesis of biologically important nitrogen compounds. The second part describes the fundamental transformations of nitrones, which will provide the strategies and means for the construction of nitrogen compounds. The reactions with nucleophiles or radicals, C–H functionalization, and various addition reactions are described. The last reactions are particularly important for highly selective carboncarbon bond formations. 1,3-Dipolar cycloaddition reactions are excluded because the size of the review is limited and excellent reviews have been published in Chemical Reviews.