A Facile Synthesis of Ethyl α-Cyano-β-amincacrylates and Related Compounds

Abstract

Ethyl-α-cyano-β-aminoacrylates (I) have been used as intermediates in the synthesis of pyrimidine derivatives^1,2 and I(R=H,CH₃, C₆H₅) have been obtained by the condensations of ethyl cyanoacetate with amidines and iminoethers, in relatively poor yields.² We now report that both biprotic and monoprotic carbothioamides-thioformamide, thiobenzamides, phenylthioacetamide, quinazolin-4(3H)-thione and pyrrolidin-2(1H)-thione condense with ethyl bromocyanoacetate, with extrusion of sulphur, to form ethyl α-cyano-β-aminoacrylate (I, R=H), ethyl α-cyano-β-aminocinnamates (I, R=-C₆H₅,-C₆H₄-OCH₃, -C₆H₄-NO₂,P), ethyl α -cyano-β-amino-β-benzylacrylate (I, R=-CH₂C₆H₅), ethyl-α-cyano Δ^4(3H), quinazolineace tate (II) and ethyl α-cyano-Δ^2,α pyrrolidineacetate (III) (Table) respectively.