Pyrido benzopyrans

In other somewhat related work, the synthesis of pyrano[2,3-c]azepines (and pyrido[2,3-c]azepines has been described. Reaction of hydrazoic with iV-(5,6,7.8-tetrahydro-2,5-dioxo-2W-l-benzopyran-3-yl)benzamide (or 8-hydrazono) derivatives afforded pyrano[2,3-c]azepines, which in turn can be transformed to pyrido[2,3-c]azepines <00H(53)1111>. 

Base-catalyzed rearrangement of Af-(aryloxy)pyridinium salts (11) leads to 2-arylpyridines (12) via intramolecular attack on the ortho position of the aryloxy ring by the 2-pyridyl carbanion. When X was 3-CChMe, pyrido[3,2-J]coumarins (13 R = NO2, CN) were directly obtained in useful yields from this reaction. When in (11) X was 3-COMe and R was 4-NO2, 10-hydroxy- 10-methyl-6-nitropyrido[2,3-J]benzopyran (14) was obtained in 10.8% yield.89... 

Benzo[g indol 2,3-Dioxo-6-mtro-2,3-dihydro- VII/4, 16 5H-[Pg.956]

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