The reactions of some pyraiiylideneiminium salts with amines. II

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Abstract
The iminium salt, N,N‐dimethyl‐N‐[2‐(2‐phenyl‐4H‐l‐benzopyran‐4‐ylidene)ethylidene] imin‐ium perchlorate (3), reacts with secondary amines by exchanging the dimethylimino group for the added amine. Primary amines also reacted with 3 in the same manner. The bis iminium salts, N,N,N',N'‐tetramethyl‐N,N'‐[2‐(2‐phenyl‐4H‐l‐benzopyran‐4‐ylidene)‐1,3‐propanediylidene]‐bis(immium perclilorate) (4) and the corresponding thiapyran derivative (5), react with ammonia to give 5‐dimethylamino‐2‐phenyl‐5H‐1‐benzopyrano[3,4‐c]pyridine (10) and the thia analog 11. The reactions of 4 and 5 with primary amines give 3‐alkyl‐5‐dimethylamino‐2‐phenyl‐5H‐l‐beiizopyrano[3,4‐c]pyridinium perclilorate salts or the corresponding thiapyrano compounds. Compounds 4 and 5 react with secondary amines by exchanging the dimethylimino groups with the secondary amine and addition of the amine at the 2‐position of the pyran or thiapyran ring.