Patra Koushik, Dey Manas Pratim, Baidya Mahiuddin
Department of Chemistry, Indian Institute of Technology Madras Chennai 600 036 Tamil Nadu India
Chem Sci. 2024 Sep 13;15(40):16605-11. doi: 10.1039/d4sc04108a.
While hypervalent halogens are versatile reagents enabling diverse reactions in organic synthesis, the utility of hypervalent chlorine compounds, particularly cyclic λ-chloranes, remains underdeveloped despite their unique electronic properties and innate enhanced reactivity. Herein, we illustrate the elusive ligand coupling reaction of cyclic λ-chloranes that suppresses the more facile competing reaction modality involving benzyne intermediates. The methodology can be performed in three-component as well as two-component fashions, offering direct access to a wide range of unsymmetrically substituted biaryl molecules in very high yields and excellent -regioselectivity. The reactions were scalable, and the versatility was demonstrated by constructing different types of C-S and C-N bonds under mild conditions. The reaction outcomes were also compared with those of corresponding λ-iodanes and λ-bromanes, demonstrating the superiority of cyclic λ-chloranes in ligand-coupling reactions under metal-free conditions.
虽然高价卤素是有机合成中能实现多种反应的通用试剂，但尽管高价氯化合物，特别是环状λ-氯烷具有独特的电子性质和固有的增强反应活性，其应用仍未得到充分开发。在此，我们展示了环状λ-氯烷难以捉摸的配体偶联反应，该反应抑制了涉及苯炔中间体的更易发生的竞争反应模式。该方法可以以三组分和双组分的方式进行，能够以非常高的产率和优异的区域选择性直接获得各种不对称取代的联芳基分子。这些反应具有可扩展性，并且通过在温和条件下构建不同类型的C-S和C-N键证明了其通用性。还将反应结果与相应的λ-碘烷和λ-溴烷的结果进行了比较，证明了环状λ-氯烷在无金属条件下的配体偶联反应中的优越性。
