Aerobic oxidation reactions have been the focus of considerable attention, but their use in mainstream organic chemistry has been constrained by limitations in their synthetic scope and by practical factors, such as the use of pure O2 as the oxidant or complex catalyst synthesis. Here, we report a new (bpy)CuI/TEMPO catalyst system that enables efficient and selective aerobic oxidation of a broad range of primary alcohols, including allylic, benzylic, and aliphatic derivatives, to the corresponding aldehydes using readily available reagents, at room temperature with ambient air as the oxidant. The catalyst system is compatible with a wide range of functional groups and the high selectivity for 1° alcohols enables selective oxidation of diols that lack protecting groups.

Highly practical copper(I)/TEMPO catalyst system for chemoselective aerobic oxidation of primary alcohols.

Organosulfur compounds have long played a vital role in organic chemistry and in the development of novel chemical structures and architectures. Prominent among these organosulfur compounds are those involving a sulfur(IV) center, which have been the subject of countless investigations over more than a hundred years. In addition to a long list of textbook sulfur-based reactions, there has been a sustained interest in the chemistry of organosulfur(IV) compounds in recent years. Of particular interest within organosulfur chemistry is the ease with which the synthetic chemist can effect a wide range of transformations through either bond formation or bond cleavage at sulfur. This review aims to cover the developments of the past decade in the chemistry of organic sulfur(IV) molecules and provide insight into both the wide range of reactions which critically rely on this versatile element and the diverse scaffolds that can thereby be synthesized.

Bond-Forming and -Breaking Reactions at Sulfur(IV): Sulfoxides, Sulfonium Salts, Sulfur Ylides, and Sulfinate Salts.

An overview of reactive gold α-oxo carbenoid intermediates in the gold-catalyzed functionalization of alkynes is presented. Such intermediates can be generated from inter- and intramolecular oxidation of alkynes by nucleophilic oxygen-atom donor groups, such as amine N-oxides, pyridine N-oxides, nitrones, nitro compounds, sulfoxides, and epoxides. These O-atom transfer processes occur by gold-mediated addition-elimination reactions. In catalytic systems, α-oxo carbenoids can undergo nucleophilic attack by imine, arene, and migrating hydride as well as alkyl groups, leading to cascade reactions and the construction of new skeletons. The facile construction of C-E (E=C, N, S, or O) bonds makes it an attractive step-economic approach to value-added molecules from readily available starting materials. The scope, mechanisms, and reactivity of such α-oxo carbenoid species are discussed. The remarkable diversity of structures accessible is demonstrated with various recent examples.

Gold α-Oxo Carbenoids in Catalysis: Catalytic Oxygen-Atom Transfer to Alkynes

Formal [4+1] Annulation Reactions in the Synthesis of Carbocyclic and Heterocyclic Systems

Dimethyl sulfoxide (DMSO) is one of the most commonly applied organic solvents in chemical transformations and is utilized widely in industrial processes as well. During the past decades, numerous procedures using DMSO as a reaction reagent have been developed and published. In this review, the main developments on the employment of DMSO as sources of Me, SMe, SO2Me, as an oxidant etc. have been summarized and discussed.

The Applications of Dimethyl Sulfoxide as Reagent in Organic Synthesis

The current review is intended to emphasize the most important developments in the use of activated DMSO for the oxidation of alcohols since 1981 through 1989, but includes sufficient coverage of the earlier literature so as to be self-contained. Only enough of the vast number of recent references are cited to highlight advances in the methodology and to provide recent examples of the application of these reactions.

Thomas T. Tidwell

Papers

Oxidation of Alcohols by Activated Dimethyl Sulfoxide and Related Reactions: An Update

Oxidation of Alcohols by Activated Dimethyl Sulfoxide and Related Reactions: an Update

Allenylketenes: Versatile Substrates in Nucleophilic, Electrophilic, and Cycloaddition Reactions

Allenylketenes: Versatile Substrates in Nucleophilic, Electrophilic, and Cycloaddition Reactions