Li Shao-Gang, Chen Hui-Jun, Yang Yang-Yang, Wu Wen-Ju, Wu Yikang
State Key Laboratory of Bioorganic and Natural Products Chemistry, Collaborative Innovation Center of Chemistry for Life Sciences, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, China.
Chem Asian J. 2015 Nov;10(11):2333-6. doi: 10.1002/asia.201500728. Epub 2015 Aug 28.
A novel acid-promoted rearrangement is disclosed. In the previously unknown transformation, an allyl group migrated to an in situ formed carbocation stabilized by an electron-rich aryl or heteroaryl group, resulting in a stereoselective intramolecular Grob fragmentation. The outcome of the rearrangement observed with an array of substrates can be satisfactorily rationalized using a working hypothesis with the aid of a six-membered transition state similar to those proposed for the anionic oxy-Cope or oxonia-Cope rearrangements, but involving only one instead of two double bonds.
公开了一种新型的酸促进重排反应。在这种前所未知的转化过程中，烯丙基迁移至由富电子芳基或杂芳基稳定的原位形成的碳正离子上，从而导致立体选择性分子内格罗布碎片化反应。借助一个类似于阴离子氧杂-Cope重排或氧鎓-Cope重排所提出的六元过渡态的工作假设，但仅涉及一个而非两个双键，一系列底物的重排结果能够得到令人满意的合理解释。
