A new synthesis of 2,4-bis(dialkylamino)-pyridines and quinolines is reported. Starting from primary aryl amines or aliphatic imines a mechanism via ynamine-amidines is followed if the cyanine Ia is used as reagent. When the cyanine is substituted, (I.R. ≠ H) it reacts well in high dilution conditions via the alternate intermediates XI and XII. In the same manner, the azacyanine XV forms the pyrimidine XVII and the quinazoline XVI.
