Hemin-catalyzed sulfonium ylide formation and subsequently reactant-controlled chemoselective rearrangements
Xiaofei Xu1, Chang Li, Mingteng Xiong
1Department of Chemistry, Zhejiang University, Hangzhou 310027, People's Republic of China. cheyjpan@zju.edu.cn.
Abstract:
Hemin-catalyzed competing routes of [1,2]-Stevens and Sommelet-Hauser rearrangements of benzyl sulfonium ylides through an iron porphyrin carbenoid were established. These rearrangements can be controlled by the electronic property of the substituents on the benzyl group together with solvent effects. Electron-donating or weak electron-withdrawing groups lead to the [1,2]-Stevens rearrangement, whereas strong electron-withdrawing groups at the para-position favor the latter pathway under aqueous conditions.
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