Metal-Catalyzed Acyl Transfer Reactions of Enol Esters:  Role of Y₅(O<i>ⁱ</i>Pr)₁₃O and (thd)₂Y(O<i>ⁱ</i>Pr) as Transesterification Catalysts

Abstract

Primary and secondary alcohols react with vinyl or isopropenyl acetate at room temperature in the presence of catalytic amounts (0.05-1 mol %) of Y5(OiPr)13O to give the corresponding esters. In selected cases, the yttrium catalyst promotes the selective O-acylation of amino alcohols without the formation of the amide. Enol esters also react with alpha-amino acid esters in the absence of a catalyst, at room temperature, to give the corresponding amides.