Fluoride-catalyzed aldol reaction of ethyl trimethylsilyldiazoacetate with aldehydes leading to ethyl alpha-diazo-beta-hydroxy esters and rhodium catalyzed decarboxylative rearrangement of diazo urethanes leading to beta-amino acrylates

摘要

Ethyl trimethylsilyldiazoacetate reacts smoothly with a variety of aldehydes at 0 degrees C in the presence of a catalytic amount of tetrabutylammonium fluoride to produce alpha-diazo-beta-hydroxy esters in good to excellent yields. The resulting alpha-diazo-beta-hydroxy esters can be,stereoselectively transformed, by a sequence of carbamation with p-toluenesulfonyl isocyanate and rhodium(II)-induced decarboxylative rearrangement, to alpha- or beta-substituted beta-(p-toluenesulfonylamino)acrylates depending upon migration aptitude of the substituents derived from the aldehydes. (C) 1999 Elsevier Science Ltd. All rights reserved. [References: 14]