Merck Center for Catalysis at Princeton University , Princeton, New Jersey 08544, United States.
J Am Chem Soc. 2013 Dec 11;135(49):18323-6. doi: 10.1021/ja410478a. Epub 2013 Nov 22.
The direct β-coupling of cyclic ketones with aryl ketones has been achieved via the synergistic combination of photoredox catalysis and organocatalysis. Diaryl oxymethyl or aryl-alkyl oxymethyl radicals, transiently generated via single-electron reduction of ketone precursors, readily merge with β-enaminyl radical species, generated by photon-induced enamine oxidation, to produce γ-hydroxyketone adducts. Experimental evidence indicates that two discrete reaction pathways can be operable in this process depending upon the nature of the ketyl radical precursor and the photocatalyst.
通过光氧化还原催化和有机催化的协同组合,实现了环状酮与芳基酮的直接β-偶联。二芳基甲氧基或芳基-烷基甲氧基自由基通过酮前体的单电子还原瞬时生成,容易与由光子诱导的烯胺氧化生成的β-烯胺自由基物种合并,生成γ-羟基酮加合物。实验证据表明,在这个过程中,两种不同的反应途径可以根据酮基自由基前体和光催化剂的性质来操作。