A new chiral bicyclic guanidine-catalyzed direct catalytic aldolreaction of 5H-oxazol-4-ones with aldehydes has been developed. The present aldolreaction proceeds smoothly with high enantioselectivity using bicyclic guanidines bearing a hydroxy group at the appropriate position, and various combinations of 5H-oxazol-4-ones and aldehydes are applicable. The method provides synthetically useful alpha
Facile and Versatile Room-Temperature Synthesis of N,N-Disubstituted Cyanoacetamides from Malonic Ester Chloride
作者:Andrzej Manikowski、Zofia Kolarska
DOI:10.1080/00397910902788216
日期:2009.9.18
Abstract A generalmethod for the synthesis of various N,N-disubstituted cyanoacetamides from readily available methyl malonyl chloride and secondary amines, including sterically demanding aliphatic and aromatic amines, is described.
electrocatalytic strategy for the cyclopropanation of activemethylenecompounds, employing an organic catalyst. The method shows a broad substrate scope and excellent scalability, requires no metal catalyst or external chemical oxidant, and provides convenient access to several types of cyclopropane-fused heterocyclic and carbocyclic compounds. Mechanistic investigations suggest that the reactions