Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260 (USA).
Angew Chem Int Ed Engl. 2014 May 5;53(19):4926-9. doi: 10.1002/anie.201402010. Epub 2014 Apr 7.
Allylic alcohols undergo transposition reactions in the presence of Re2 O7 whereby the equilibrium can be dictated by trapping one isomer with a pendent electrophile. Additional ionization can occur when the trapping group is an aldehyde or ketone, thus leading to cyclic oxocarbenium ion formation. Terminating the process through bimolecular nucleophilic addition into the intermediate provides a versatile method for the synthesis of diverse oxygen-containing heterocycles. Understanding the relative rates of the steps in the sequence leads to the design of reactions which create multiple stereocenters with good to excellent levels of control.
烯丙醇在 Re2O7 的存在下发生位移反应，通过用一个末端亲电试剂捕获一种异构体，可以控制平衡。当捕获基团是醛或酮时，会发生额外的电离，从而导致环状氧杂碳正离子的形成。通过双分子亲核加成到中间体中终止该过程，为合成各种含氧杂环提供了一种通用的方法。了解序列中各步的相对速率可以设计出具有良好到极好控制水平的多立体中心反应。
