A novel synthesis of substituted 6-phenylpyrano[2,3-c]pyrazol-4(1H)-ones via reaction of various 2-substituted or 2,5-disubstituted 2,4-dihydro-3H-pyrazol-3-ones with phenylpropynoyl chloride using calcium hydroxide in refluxing 1,4-dioxane is described. N-Unsubstituted representatives were obtained by treatment of 4-methoxybenzyl-protected congeners with trifluoroacetic acid.

中文翻译：

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6-Phenylpyrano[2,3-c]pyrazol-4(1H)-ones 的简单合成

通过各种 2-取代或 2,5-二取代 2,4-二氢-3H-吡唑-3-酮与描述了在回流 1,4-二恶烷中使用氢氧化钙的苯丙酰氯。N-未取代的代表是通过用三氟乙酸处理 4-甲氧基苄基保护的同系物获得的。