A thermally induced novel formal [4+2] cycloaddition of cyclobutenones with electron-deficient alkynes under metal-free conditions has been developed for the first time. The reaction can proceed in a highly regioselective manner and provides a straightforward and efficient method for the synthesis of 4-pyridone derivatives from readily available starting materials in a single step.

中文翻译：

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热诱导的3-氨基环丁烯与电子缺陷型炔烃的正式[4 + 2]环加成反应：高效合成4-吡啶酮†

在无金属条件下，首次开发了一种热诱导的新的环丁烯酮与缺电子炔烃的正式[4 + 2]环加成反应。该反应可以以高度区域选择性的方式进行，并提供了一种简单有效的方法，可在一个步骤中从容易获得的起始原料合成4-吡啶酮衍生物。