Pan Yue, Jia Kunfang, Chen Yali, Chen Yiyun
Department of Chemistry, Shanghai University, 99 Shangda Road, Shanghai 200444, China.
State Key Laboratory of Bioorganic and Natural Products Chemistry, Centre for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China.
Beilstein J Org Chem. 2018 May 28;14:1215-1221. doi: 10.3762/bjoc.14.103. eCollection 2018.
The alkynylbenziodoxole derivatives are recently developed alkynylation reagents in organic synthesis, which demonstrate excellent radical alkynylation reactivity in photoredox catalysis reactions. Herein we report the synthesis of alkynylbenziodoxole derivatives with difluoro, monofluoro, monomethoxy, and dimethoxy substitution on the benziodoxole moiety, and investigated their radical alkynylation reactivity for the first time. A series of mechanistic experiments were conducted to study the radical acceptor and oxidative quencher reactivity of alkynylbenziodoxoles, in which unsubstituted alkynylbenziodoxoles played balancing roles in both processes, while electron-rich benziodoxole derivatives demonstrate synthetic advantages in some cases.
炔基苯并碘恶唑衍生物是近年来在有机合成中开发的炔基化试剂，在光氧化还原催化反应中表现出优异的自由基炔基化反应活性。在此，我们报道了在苯并碘恶唑部分具有二氟、单氟、单甲氧基和二甲氧基取代的炔基苯并碘恶唑衍生物的合成，并首次研究了它们的自由基炔基化反应活性。进行了一系列机理实验来研究炔基苯并碘恶唑的自由基受体和氧化猝灭剂反应活性，其中未取代的炔基苯并碘恶唑在这两个过程中都起到了平衡作用，而富电子的苯并碘恶唑衍生物在某些情况下表现出合成优势。
