Synthesis of 4-hydroxy-5-methyl-2-[2-(4-oxo-4H-chromen-3-yl)ethenyl]-6H-1,3-oxazin-6-ones and their reaction with hydrazine
作者:N. M. Chernov、A. S. Klyukin、G. V. Ksenofontova、A. E. Shchegolev、I. P. Yakovlev
DOI:10.1134/s1070363217050103
日期:2017.5
4-Hydroxy-6H-1,3-oxazin-6-ones containing a 3-vinylchromone fragment in the 2-position were synthesized. The direction of their reactions with hydrazine hydrate was found to depend on the solvent nature. The reaction in protic solvents (methanol, acetic acid) resulted in recyclization of both oxazine ring to 1,2,4-triazole and pyranone ring to pyrazole. Aprotic acetonitrile favored attack of hydrazine
合成了在2-位含有3-乙烯基色酮片段的4-羟基-6 H -1,3-恶嗪-6-酮。发现它们与水合肼的反应方向取决于溶剂性质。在质子溶剂(甲醇,乙酸)中的反应导致恶嗪环同时环化为1,2,4-三唑和吡喃酮环均环化为吡唑。非质子的乙腈只支持肼对恶嗪环的攻击,而3-乙烯基色酮片段则保持完整。