Oxidative rearrangement of 1,1-disubstituted alkenes to ketones

• 成果类型: Article
• 署名作者: Feng, Qiang; Wang, Qian; Zhu, Jieping
• 署名单位: Swiss Federal Institutes of Technology Domain; Ecole Polytechnique Federale de Lausanne
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-13141
• DOI: 10.1126/science.adg3182
• 发表日期: 2023-03-31
• 页码: 1363-1368
• 关键词: thallium(iii) oxidation; ring enlargements

摘要

The Wacker process, which is widely used to convert monosubstituted alkenes into the corresponding methyl ketones, is thought to proceed through a PdII/Pd0 catalytic cycle involving a b-hydride elimination step. This mechanistic scenario is inapplicable to the synthesis of ketones from the 1,1-disubstituted alkenes. Current approaches based on semi-pinacol rearrangement of PdII intermediates are limited to the ring expansion of highly strained methylene cyclobutane derivatives. Herein, we report a solution to this synthetic challenge by designing a PdII/PdIV catalytic cycle incorporating a 1,2-alkyl/PdIV dyotropic rearrangement as a key step. This reaction, compatible with a broad range of functional groups, is applicable to both linear olefins and methylene cycloalkanes, including macrocycles. Regioselectivity favors the migration of the more substituted carbon, and a strong directing effect of the b-carboxyl group was also observed.