4H-[1]苯并吡喃[3,4-d]异噁唑-4-酮的合成(英文)

Synthesis of 4H-[1]Benzopyrano[3,4-d]isoxazol-4-ones

芳酰乙酸乙酯在乙氧基镁的作用下与取代的苯甲酰氯反应生成2-取代苯并吡喃酮。2-取代苯并吡喃酮和盐酸羟胺经Beckmann重排反应合成了4H-[1]苯并吡喃[3,4-d]异噁唑-4-酮。X衍射谱图表明,反应过程中表现区域选择性。对该反应的反应机理进行了初探。

Ethyl benzoylacetate reacted with acetylsalicyloyl chloride in the presence of magnesium ethylate and ethyl 2-aryl-4-oxo-4H-[1]benzopyran-3-carbonate were gained,which reacted with hydroxylamine via Beckmann rearrangement and 4H-[1]benzopyrano[3,4-d]isoxazol-4-ones were gained.X-Ray analysis result of compound 2b confirmed the regioselectivity of the reaction.The mechanism of the formation of 4H-[1] benzopyrano[3,4-d]isoxazol-4-ones is also investigated.