Direct Catalytic Enantioselective α-Aminoxylation of Ketones: A Stereoselective Synthesis of α-Hydroxy and α,α'-Dihydroxy Ketones

摘要

One of the ultimate goals and challenges in chemistry is to develop catalytic stereoselective transformations for the creation of optically active molecules from simple and easily available starting materials. Optically active α-hydroxy carbonyl moieties are commonly found in numerous important natural products. This has led to extensive research to find new diastereoselective and enantioselective routes for their syntheses. One way of preparing these compounds is the asymmetric α-hydroxylation of enolates. Despite extensive research in this area it was not until recently that Yamomoto et al. reported a more efficient catalytic system based on AgX/binap complexes (binap=2,2'-bis(diphenylphosphanyl)-1,1'-binaphthyl), which mediate indirect α-oxidation of activated tin enolates.