Regiochemistry in 1,3-dipolar cycloadditions of the azomethine ylide formed from diethyl aminomalonate and paraformaldehyde.

J Org Chem

Center for New Directions in Organic Synthesis, Department of Chemistry, University of California, Berkeley, California 94720, USA.

Published: January 2002

The azomethine ylide derived from the condensation of diethyl aminomalonate with paraformaldehyde undergoes 1,3-dipolar cycloadditions with acrylate and propiolate derivatives. Contrary to a previous report, these reactions yield mixtures of regioisomers generally favoring the 2,2,3-trisubstituted product. However, the relative quantity of the 2,2,4-trisubstituted product formed increases with an increase in the size of the activating group on the dipolaroplile.

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http://dx.doi.org/10.1021/jo010645xDOI Listing

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