Development of Chiral Ureates as Chiral Strong Brønsted Base Catalysts.

Abstract

Recently, chiral Brønsted bases having high basicity have emerged as a powerful tool in developing new catalytic enantioselective reactions. However, such chiral strong Brønsted base catalysts are still very scarce. Herein, we report the development of a chiral anionic Brønsted base having a N,N'-dialkyl ureate moiety as a basic site. Its prominent catalytic activity was demonstrated in the enantioselective addition reactions of α-thioacetamides as less acidic pronucleophiles with various electrophiles. Thus, the newly developed chiral catalyst with high accessibility and structural tunability would expand the scope of viable enantioselective transformations under Brønsted base catalysis.