The carbon-carbon double bond, with its diverse and multifaceted reactivity, occupies a prominent position in organic synthesis. Although a variety of simple alkenes are readily available, the mild and chemoselective introduction of a unit of unsaturation into a functionalized organic molecule remains an ongoing area of research, and the olefination of carbonyl compounds is a cornerstone of such approaches. Here we show the direct olefination of hydrazones via the intermediacy of three-membered ring species generated by addition of sulfoxonium ylides, departing from the general dogma of alkenes synthesis from carbonyls. Moreover, the mild reaction conditions and operational simplicity of the transformation render the methodology appealing from a practical point of view.

中文翻译：

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三元环方法进行羰基烯化。

碳-碳双键具有多样化和多方面的反应性，在有机合成中占有重要地位。尽管可以容易地获得各种简单的烯烃，但是将不饱和单元温和和化学选择性地引入官能化的有机分子中仍然是研究的一个领域，并且羰基化合物的烯化是这种方法的基石。在这里，我们展示了via的直接烯烃加成反应，是通过三元环物种之间的中间直接加成of砜生成的，这些三元环物种是由羰基合成烯烃的一般教义所引起的。而且，温和的反应条件和转化的操作简便性使得该方法从实用的角度来看具有吸引力。