Nitrosoallene-mediated endo-dig cyclization reactions producing (hetero)cyclic exo-unsaturated oximes (enoximes) are described. The intramolecular 1,4-type addition to in situ generated nitrosoallenes afforded α-substituted cyclic enoximes with exo-methylene units, which are the favored conformation for further cyclizations. The strong electron-withdrawing ability of the nitroso group facilitated the construction of five-to-seven-membered ring systems via C–O, C–N, C–S, and C–C bond formations, including a quaternary carbon center, at low temperatures.

中文翻译：

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Nitrosoallene介导的内用于合成（杂）环状-Cyclizationsα取代型外切不饱和肟

描述了亚硝基亚砜介导的内-dig环化反应，其产生（杂）环外-不饱和肟（烯肟）。分子内的1，4-型加成到原位生成的亚硝基亚芳基得到具有外亚甲基单元的α-取代的环烯，这是用于进一步环化的有利构象。亚硝基的强大的吸电子能力通过C–O，C–N，C–S和C–C键的形成（包括一个季碳中心）促进了五至七元环系统的构建。低温。