1,2,4-三唑并[3,2-d][1,5]-苯并氧氮杂化合物的合成

Synthesis of 1,2,4-Triazolo[3,2-d][1,5]benzoxazepine Compounds

苯并二氢吡喃 4 酮的芳腙 (1 )衍生的偶氮基碳正离子 (3)与腈发生 1 ,3 偶极环加成反应 ,加成产物 (4 )通过 [1 ,2 ] 迁移扩环重排反应 ,形成新颖的三环系杂环化合物 1 ,2 ,4 三唑并 [3,2 d][1 ,5 ] 苯并氧氮杂化合物 5a_5k .

Azocarbenium ions 3, prepared in situ from 4-chromanone arylhydrazones 1, cycloadd readily to the triple bond of nitriles forming 3-spiro substituted 1,2,4-triazolium salts 4. The initial cycloadducts 4 cannot be isolated but undergo consecutive reactions, e.g. [1,2]-shifts and ensuing ring enlargement to provide 1,2,4-triazolo[3,2-d][1,5]benzoxazepine compounds 5a—5k, a kind of novel tricyclic heterocycles.