A metal-free base-promoted [4+3] cycloaddition reaction of N-thioacyl imines in situ generated from α-amido sulfones with α-chlorohydroxamates is described. The reaction allows the straightforward synthesis of 1,3,5-thiadiazepin-6(7H)-one derivatives in 44~90% yields. Moreover, a gram-scale reaction and a product transformation were conducted, which further increased the diversity of products.

中文翻译：

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α-氯异氧肟酸盐的 N-硫代酰亚胺的碱促进 [4+3] 环加成反应：1,3,5-硫二氮卓-6（7H）-酮衍生物的构建

描述了由 α-酰胺基砜与 α-氯异氧肟酸盐原位生成的 N-硫酰基亚胺的无金属碱促进 [4+3] 环加成反应。该反应允许以 44~90% 的产率直接合成 1,3,5-噻二氮卓-6（7H）-酮衍生物。此外，还进行了克级反应和产物转化，进一步增加了产物的多样性。