Martínez-Balart Pol, Velasco-Rubio Álvaro, Barbeira-Arán Sergio, Jiménez-Cristóbal Hugo, Fañanás-Mastral Martín
Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS), Universidade de Santiago de Compostela 15782 Santiago de Compostela Spain
Green Chem. 2024 Oct 4;26(22):11196-11205. doi: 10.1039/d4gc04176c. eCollection 2024 Nov 11.
-Difluoroalkenes and trifluoromethyl alkanes are prominent structures in biologically active compounds. Radical alkylation of α-trifluoromethyl alkenes represents a useful strategy to access these structures. However, reported methods have relied on the use of pre-functionalized radical precursors and examples involving the use of simple hydrocarbons as coupling partners are elusive. Here we report a chemodivergent methodology based on the direct activation of C(sp)-H bonds enabled by HAT photoredox catalysis. This protocol provides an efficient platform for preparing both -difluoroalkenes and trifluoromethyl alkanes from ubiquitous hydrocarbon feedstocks, including gaseous alkanes. Importantly, chemoselectivity is easily achieved by simple modification of reaction conditions and/or additives.
二氟烯烃和三氟甲基烷烃是生物活性化合物中的重要结构。α-三氟甲基烯烃的自由基烷基化是获得这些结构的一种有用策略。然而,已报道的方法依赖于使用预官能化的自由基前体,而涉及使用简单烃类作为偶联伙伴的例子却很少见。在这里,我们报道了一种基于HAT光氧化还原催化直接激活C(sp)-H键的化学发散方法。该协议为从常见的烃类原料(包括气态烷烃)制备二氟烯烃和三氟甲基烷烃提供了一个有效的平台。重要的是,通过简单改变反应条件和/或添加剂很容易实现化学选择性。