Rapid Ligations with Equimolar Reactants in Water with the Potassium Acyltrifluoroborate (KAT) Amide Formation
作者:Hidetoshi Noda、Gábor Erős、Jeffrey W. Bode
DOI:10.1021/ja5018442
日期:2014.4.16
The identification of fast, chemoselective bond-forming reactions is one of the major contemporary challenges in chemistry. We show that chemoselective amide-formingligations of potassium acyltrifluoroborates (KATs) and O-carbamoylhydroxylamines proceed in the presence of all unprotected functional groups with a second-order rate constant of 20 M(-1) s(-1). PEG chains, lipids, biotin, and dyes were
the oxime functional group played a key role in both the ease by which the oxime could be reduced and the subsequent reactivity of the respective hydroxylamine. Reaction of the respective hydroxylamines with pyruvic acid derivatives generated the desired amides in good yields. A comparison of phenethylamine systems bearing different leavinggroups revealed significant differences in the rates of these