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DOI: 10.1055/s-1996-4160
Reactions of N-Unsubstituted 4-Amino-1-azadienes Towards Electrophiles
Publikationsverlauf
Publikationsdatum:
31. Dezember 2000 (online)
![](https://www.thieme-connect.de/media/synthesis/199601/lookinside/thumbnails/10.1055-s-1996-4160-1.jpg)
Several reactions related to the ambident nucleophilicity of N-unsubstituted azadienes 1 are described. Thus, reaction of 1 with alkylating agents and iodobispyridinium tetrafluoroborate (IPy2BF4) leads to the C-substituted azadienes 3 and 5 respectively. Azadienes 1 and 3 are converted to the carbonyl derivatives 2 and 4 by mild hydrolysis. On the other hand, azadienes 1, 3 and 5 react through the nitrogen atoms with several carbonyl centered electrophiles to give nitrogen heterocycles such as pyrimidines 6 and 9 and dihydropyrimidines 11. All those processes are totally regioselective, azadienes 1 and 3 showing a lower nucleophilicity at nitrogen than N-substituted azadienes.
N-unsubstituted 4-amino-1-azadienes - C-alkylation - pyrimidines - 2,3-dihydropyrimidines