Department of Chemistry, Queen's University, 90 Bader Lane, Kingston, ON, K7L 3N6, Canada.
Department of Chemistry, University of Liverpool, Crown Street, Liverpool, L69 7ZD, UK.
Angew Chem Int Ed Engl. 2018 Jan 15;57(3):673-677. doi: 10.1002/anie.201709059. Epub 2017 Dec 20.
Reported is the first example of a rhodium-mediated β-sulfide elimination, which represents a new mode of reactivity for late-transition-metal chemistry. This serendipitous discovery facilitates an ene-cycloisomerization of allylic-sulfide-containing alkenylidenecyclopropanes (ACPs) to afford five-membered carbo- and heterocyclic rings with concomitant intramolecular thioether migration. Interestingly, similar selectivity is obtained with both E- and Z-allylic sulfides and the reaction is also feasible with an allylic selenide. Mechanistic studies are consistent with an inner-sphere transfer of the sulfide, which is remarkable given the propensity for sulfides to poison transition-metal catalysts. Finally, this type of atom-economical rearrangement is envisioned to prompt the development of related processes given the utility of sulfides in target-directed synthesis.
报道了首例铑介导的β-硫醚消除反应，这代表了晚期过渡金属化学的一种新反应模式。这一偶然发现促进了含烯丙基硫醚的烯丙基烯丙基环丙烷（ACPs）的ene-环异构化反应，生成了具有伴随的分子内硫醚迁移的五元碳环和杂环。有趣的是，E-和 Z-烯丙基硫醚都具有相似的选择性，并且反应也适用于烯丙基硒醚。 机理研究与硫醚的内球转移一致，鉴于硫醚倾向于使过渡金属催化剂中毒，这一点非常引人注目。最后，鉴于硫醚在靶向合成中的用途，这种类型的原子经济性重排有望促使相关工艺的发展。
