The unexpected rearrangement of N-allyl-2-phenyl-4,5-dihydrooxazole-4-carboxamides in the presence of LiHMDS has been found. The key features are: (1) the net reaction consisted of 1,3-migration of the N-allyl group, (2) the rearrangement produced a congested aza-quaternary carbon center, (3) both cyclic and acyclic substrates underwent the unexpected rearrangement to afford products in moderate to high yields, and (4) the reaction seemed to be highly stereoselective. In addition, a plausible mechanism has been discussed.

中文翻译：

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意外重排 N-Allyl-2-phenyl-4,5-Dihydrooxazole-4-Carboxamides 以构建 Aza-Quaternary Carbon 中心

已发现在 LiHMDS 存在下 N-allyl-2-phenyl-4,5-dihydrooxazole-4-carboxamides 的意外重排。主要特征是：（1）净反应由 N-烯丙基的 1​​,3-迁移组成，（2）重排产生了一个拥挤的氮杂季碳中心，（3）环状和非环状底物都经历了意想不到的重排以提供中等至高产率的产物，以及 (4) 反应似乎具有高度立体选择性。此外，还讨论了一个合理的机制。