Sheta Ahmed M, Alkayal Anas, Mashaly Mohammad A, Said Samy B, Elmorsy Saad S, Malkov Andrei V, Buckley Benjamin R
Department of Chemistry, Loughborough University, Loughborough, Leicestershire, LE11 3TU, UK.
Department of Chemistry, Damietta University, Damietta El-Gadeeda City, Kafr Saad, Damietta Governorate, 34511, Egypt.
Angew Chem Int Ed Engl. 2021 Sep 27;60(40):21832-21837. doi: 10.1002/anie.202105490. Epub 2021 Sep 6.
The carboxylation of low-value commodity chemicals to provide higher-value carboxylic acids is of significant interest. Recently alternative routes to the traditional hydroformylation processes that used potentially toxic carbon monoxide and a transition metal catalyst have appeared. A significant challenge has been the selectivity observed for olefin carboxylation. Photochemical methods have shown a viable route towards the hydrocarboxylation of α,β-unsaturated alkenes but rely on the use of an excess reducing or amine reagent. Herein we report our investigations of an electrochemical approach that is able to hydrocarboxylate α,β-unsaturated alkenes with excellent regioselectivity and the ability to carboxylate hindered substrates to afford α-quaternary center carboxylic acids. The reported process requires no chromatography and the products are purified by simple crystallization from the reaction mixture after work-up.
将低价值的商品化学品羧化以提供高价值的羧酸具有重大意义。最近，出现了替代传统氢甲酰化工艺的路线，传统工艺使用了具有潜在毒性的一氧化碳和过渡金属催化剂。一个重大挑战是烯烃羧化反应的选择性。光化学方法已显示出一条通往α,β-不饱和烯烃氢羧化反应的可行途径，但依赖于使用过量的还原试剂或胺试剂。在此，我们报告了我们对一种电化学方法的研究，该方法能够以优异的区域选择性对α,β-不饱和烯烃进行氢羧化反应，并能够将受阻底物羧化以得到α-季碳中心羧酸。所报道的方法无需柱色谱法，产物在处理后通过从反应混合物中简单结晶进行纯化。
