A diastereoselective addition and rearrangement reaction has been developed for the synthesis of pyrrolidine-2-ylidenes from NH-isoxazolines and electron-deficient allenes. This method proceeds via the rearrangement of a proposed N-alkenylisoxazoline intermediate to generate densely functionalized pyrrolidine-2-ylidenes under simple catalyst-free conditions that tolerate ketone substituents and install relative stereochemistry at positions 3 and 4 of the heterocycle. Reaction optimization and the substrate scope are described in addition to studies evaluating the reactivity of the gem-dione and enaminone groups of the products.

中文翻译：

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由异恶唑啉和丙烯合成吡咯烷-2-亚基化物


已经开发了一种非对映选择性加成和重排反应，用于从 NH-异恶唑啉和缺电子丙烯合成吡咯烷-2-亚基化物。该方法通过重排拟议的 N-烯基异恶唑啉中间体进行，在简单的无催化剂条件下生成密集官能化的吡咯烷-2-亚酰亚胺，该条件耐受酮取代基并在杂环的位置 3 和 4 安装相对立体化学。除了评估产物的 gem-dione 和 enaminone 基团的反应性的研究外，还描述了反应优化和底物范围。