Push-pull-Butadiene. II [1]. Reaktionen von 2-Aryl-4,4-bis(methylthio)buta-1,3-dien-1,1-dicarbonitrilen mit Malononitril und Cyanessigsäure-ethylester

Push-pull-Butadienes. II. Reactions of 2-Aryl-4,4-bis(methylthio)-1,3-butadiene-1,1-dicarbonitriles with Malononitrile and Ethyl Cyanoacetate 2-Aryl-4,4-bis(methylthio)-1,3-butadiene-1,1-dicarbonitriles 1 react with sodium salts of malononitrile or ethyl cyanoacetate 3 to give 4-aryl-2-methylthio-1,4-pentadiene-1,1,5,5-tetracarbonitriles and ethyl-4-aryl-1,5,5-tricyano-2-methylthio-1,4-pentadienecarboxylates 4 , respectively. Also, arylethylidenemalononitriles 5 and bis(methylthio)methylenemalononitrile or ethyl bis(methylthio)methylenecyanoacetate 6 afford 4 . Substituted dihydropyridines 8 are prepared by treating 4 with aromatic amines. Compounds 4 d, e can be converted to 2-amino-6-aryl-4-methylthio-benzene-1,3-dicarbonitriles 11 a, b .