Ethyl-α-cyano-β-aminoacrylates (I) have been used as intermediates in the synthesis of pyrimidine derivatives1,2and I(R=H,CH3, C6H5) have been obtained by the condensations of ethyl cyanoacetate with amidines and iminoethers, in relatively poor yields.2We 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 Δ4(3H), quinazolineace tate (II) and ethyl α-cyano-Δ2,αpyrrolidineacetate (III) (Table) respectively.