Keto-Difluoromethylation of Aromatic Alkenes by Photoredox Catalysis: Step-Economical Synthesis of α-CF<sub>2</sub>H-Substituted Ketones in Flow
作者:Yoshiki Nakayama、Gaku Ando、Manabu Abe、Takashi Koike、Munetaka Akita
DOI:10.1021/acscatal.9b01312
日期:2019.7.5
sulfone-based CF2H reagents. The present photocatalytic keto-difluoromethylation has been applied to flow synthesis and easily scaled up to gram-scale synthesis within a reasonable reaction time. Furthermore, potentials of the α-CF2H-substituted ketones for useful synthetic intermediates are shown; e.g., synthesis of the CF2H-containing α-hydroxyamide with the same carbon skeleton as that of the anticonvulsant
对于α-CF的合成阶梯经济的方法2由容易获得的原料烯烃H-取代的酮已经研制成功。芳烃的自由基二氟甲基化结合DMSO氧化和光氧化还原催化是成功转化的关键。电化学分析,激光闪光光解(LFP)和密度泛函理论(DFT)计算表明,在类似的基于砜的CF 2中,N-甲苯磺酰基-S-二氟甲基-S-苯基亚砜基亚胺是最好的CF 2 H自由基源。H试剂。本光催化的酮-二氟甲基化已被用于流动合成,并在合理的反应时间内容易按比例放大至克级合成。此外,α-CF的电势2为有用的合成中间体H-取代的酮被示出; 例如,公开了具有与抗惊厥活性CF 3-类似物相同的碳骨架的含CF 2 H的α-羟基酰胺的合成。此外,还详细讨论了机理研究。