Utility of bis(methylthio)methylene malononitrile as a synthon in the synthesis of new poly-functionalized cyanoiminopyrimidines

A new series of 4-(alkyl/arylamino)-6-amino-5-cyano-2-cyanoimino-1H-pyrimidine was obtained via one-pot three-component reaction of bis(methylthio)methylene malononitrile, primary amines, and cyanoguanidine using sodium ethoxide as basic catalyst. The same new products were prepared by classical route via reaction of (alkyl/arylamino)(methylthio)methylene malononitrile with cyanoguanidine in presence of sodium ethoxide. In absence of amines, bis(methylthio)methylene malononitrile reacts directly with cyanoguanidine in presence of sodium ethoxide to give 4-ethoxy-2-cyanoimino-1H-pyrimidine. On the other hand, multicomponents reaction of bis(methylthio)methylene malononitrile with cyanoguanidine and binucleophilic β-hydroxyamines and/or ortho-phenylenediamine gave perspective 4-methyl- and/or 5-methyl-1,3-oxazolidin-2-ylidenemalononitrile and 1,3-dihydro-2H-benzimidazol-2-ylidenemalononitrile, which are inactive compounds toward reaction with cyanoguanidine to give the expected 4-(alkyl/arylamino)-2-cyanoimino-1H-pyrimidines.