Reactions of 5-aminoisoxazoles with α,β-unsaturated ketones in t-butanol on heating afforded 4,7-dihydroisoxazolo [5,4-b]pyridines. However, when the reactions were carried out at 20° using ethylene glycol as the solvent, the kinetically controlled amino adducts were obtained in excellent yields. The amino adducts were converted into the thermodynamically controlled 4,7-dihydroisoxazolo[5,4-b]pyridines by heating. Tentative mechanisms for the reactions are also presented.

中文翻译：

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二氢吡啶衍生物-I：4,7-二氢异恶唑并[5,4-b]吡啶的研究

5-氨基异恶唑与叔丁醇中的α，β-不饱和酮加热反应，得到4，7-二氢异恶唑并[5，4-b]吡啶。然而，当使用乙二醇作为溶剂在20°下进行反应时，以优异的产率获得了动力学控制的氨基加合物。通过加热将氨基加合物转化为热力学控制的4，7-二氢异恶唑并[5，4-b]吡啶。还提出了反应的暂定机理。