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An ion-pair catalyst promotes the enantioselective Baeyer—Villiger oxidation of 3-substituted cyclobutanones to give γ-butyrolactones.

An oxidative process for the formation of amides from aldehydes or related alcohols such as (XIII) is developed.

Breathe easy: Molecular oxygen is one of the most abundant, atom-efficient, and economical oxidants. An aerobic oxidative amide formation from aldehydes and amines is reported. The method uses a catalytic amount of Co(OAc)(2) and N-hydroxysuccinimide as reaction promoters. It is applicable to chiral substrates without loss of their optical purity.

Ring closing metathesis (RCM) has emerged as a powerful tool to construct macrocyclic ring systems. However, the product distribution of monomer and oligomers is often a problem in the formation of medium to large rings. In the course of synthetic studies on the natural product radicicol and its analogs, we have found that the reaction temperature, along with concentration, has significant impact on the outcome of the product ratio. Specifically, carrying out the RCM reaction in refluxing toluene (110°C) at higher dilution affords improved yields of the monomeric macrocycle. Similar observations for another family of macrolactone natural products, the epothilones, are also reported.

Reactions of steroidal α,β-epoxy vinyl triflates in Pd-catalyzed reactions are described. Oxidative insertion of Pd0 into the C−O bond, giving vinylpalladium 12, is faster than formation of the π-a...