The first catalytic, asymmetric alpha-additions of isocyanides. Lewis-base-catalyzed, enantioselective Passerini-type reactions.
The first, catalytic, enantioselective alpha-additions of isocyanides to aldehydes have been demonstrated (Passerini-type reactions). The catalytic system of silicon tetrachloride and a chiral bisphosphoramide 5a provided high yields and good to excellent enantioselectivities for the addition of tert-butyl isocyanide to a wide range of aldehydes (aromatic, olefinic, acetylenic, aliphatic). Aqueous workup afforded the alpha-hydroxy tert-butyl amides, whereas methanolic quench followed by basic workup afforded the alpha-hydroxy methyl esters.
Denmark
Scott E
SE
Roger Adams Laboratory, Department of Chemistry, University of Illinois, 600 South Mathews Avenue, Urbana, IL 61801, USA. denmark@scs.uiuc.edu
Fan
Yu
Y