"One-pot" processes in which alcohol oxidations are combined with further elaboration of the carbonyl intermediate are reviewed. Sequential processes are briefly discussed, but most attention is centered on tandem processes; that is, oxidations carried out in the presence of a nucleophilic trapping agent, rather than those in which the trapping agent is added after the oxidation is complete. As part of this Account, a comprehensive review of the discovery of tandem oxidation processes (TOP) will be given together with applications in alkene-forming reactions, cyclopropanations, and imine, oxime, amine, and heterocycle formation.

The behavior of electron-rich alkenes in rhodium-catalyzed C–H activation/annulation reactions is investigated. Vinyl acetate emerges as a convenient acetylene equivalent, facilitating the synthesis of sixteen 3,4-unsubstituted isoquinolones, as well as select heteroaryl-fused pyridones. The complementary regiochemical preferences of enol ethers versus enol esters/enamides is discussed.

alpha-hydroxy ketones undergo manganese dioxide-mediated oxidation followed by in situ trapping with aromatic or aliphatic 1,2-diamines to give quinoxalines or dihydropyrazines, respectively, in a one-pot procedure which avoids the need to isolate the highly reactive dicarbonyl intermediates. The scope and limitations of these procedures are outlined and modifications to this procedure are discussed in which reduction is carried out in the same reaction vessel, generating piperazines, or oxidation, leading to pyrazines.

Alpha-hydroxyketones undergo MnO2-mediated oxidation followed by in situ trapping with aromatic or aliphatic 1,2-diamines to give quinoxalines or dihydropyrazines, respectively, in a one pot procedure which avoids the need to isolate the highly reactive 1,2-dicarbonyl intermediates. Modifications of the procedure allow the formation of pyrazines and piperazines.

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