Zur Synthese von Alkoxymethylenmalonitrilen,Tetracyanpropeniden und hochsubstituierten α-Aminopyridinen

Malononitrile reacts with triethyl orthoformate,-orthoacetate,-orthopropionate and-orthobenzoate, resp., in the presence of different amounts of pyridine to ethoxymethylene-malononitriles and pyridinium 1,1,3,3-tetracyano-propenides, resp. The latter can easily be cyclised to 2-amino-6-chloro-3,5-dicyano-(4-alkyl and aryl, resp.)-pyridines. The synthesis of the -aminopyridines can be carried out as one step reactions starting with malononitrile and orthoformate.