Patra Tuhin, Mukherjee Satobhisha, Ma Jiajia, Strieth-Kalthoff Felix, Glorius Frank
Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 40, 48149, Münster, Germany.
Angew Chem Int Ed Engl. 2019 Jul 29;58(31):10514-10520. doi: 10.1002/anie.201904671. Epub 2019 Jul 3.
Despite significant progress in aliphatic decarboxylation, an efficient and general protocol for radical aromatic decarboxylation has lagged far behind. Herein, we describe a general strategy for rapid access to both aryl and alkyl radicals by photosensitized decarboxylation of the corresponding carboxylic acids esters followed by their successive use in divergent carbon-heteroatom and carbon-carbon bond-forming reactions. Identification of a suitable activator for carboxylic acids is the key to bypass a competing single-electron-transfer mechanism and "switch on" an energy-transfer-mediated homolysis of unsymmetrical σ-bonds for a concerted fragmentation/decarboxylation process.
尽管在脂肪族脱羧反应方面取得了重大进展，但用于自由基芳香族脱羧反应的高效通用方法却远远滞后。在此，我们描述了一种通用策略，通过相应羧酸酯的光敏脱羧反应快速获得芳基和烷基自由基，然后将它们相继用于不同的碳-杂原子和碳-碳键形成反应中。识别合适的羧酸活化剂是绕过竞争性单电子转移机制并“开启”不对称σ键的能量转移介导均裂以实现协同碎片化/脱羧过程的关键。
