Epoxides are regarded as important pharmacophores that can have a huge effect on improving drug activity. However, epoxides with continuous quaternary centers are challenging to construct due to steric hindrance. Herein, we report a visible-light-induced cycloaddition reaction of N-tosylhydrazones with trifluoromethyl ketones to synthesize trifluoromethyl(spiro)-epoxides bearing contiguous quaternary centers under metal-free and catalyst-free conditions. This strategy could be adapted to a variety of groups and a wide range of applications, including the modification of drug derivatives and gram-scale synthesis. Furthermore, the obtained epoxides could be efficiently converted into other valuable building blocks, such as trifluoroacetone analogues.

中文翻译：

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具有连续四元中心的三氟甲基（螺）环氧化物的可见光介导无催化剂合成

环氧化物被认为是重要的药效团，对提高药物活性具有巨大作用。然而，由于空间位阻，具有连续四价中心的环氧化物的构建具有挑战性。在此，我们报道了N-甲苯磺酰腙与三氟甲基酮的可见光诱导环加成反应，在无金属和无催化剂的条件下合成带有连续四元中心的三氟甲基（螺）环氧化物。该策略可以适应各种群体和广泛的应用，包括药物衍生物的修饰和克级合成。此外，获得的环氧化物可以有效地转化为其他有价值的结构单元，例如三氟丙酮类似物。