Research Group of Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Chinese Academy of Sciences, Hu Fanghui, C2 Asymmetric Friedel-Crafts Alkylation of b, g-unsaturated-α-ketoimidate Catalyzed by Chiral Phosphate in C3 Position New progress was made in the area. Related research results were published online on January 16 in the Organic Letters (DOI: 10.1021/ol5035222).
The anthraquinone ring-containing compound is one of the most widely distributed compound series in natural products, and many drug molecules and bioactive molecules contain anthraquinone structural units. Asymmetric Friedel-Crafts alkylation is the most common method for the synthesis of optically active anthraquinone derivatives.
However, due to the fact that the nucleophilic activity of å²å“šC3 is significantly higher than other sites, most of the existing hydrazine derivatization reactions are concentrated in the C3 position of thorium. There are few studies on the C2-functionalization reaction with relatively low activity. The limitations have severely affected the application of these compounds in the synthesis of natural products and pharmacological activities. The team used BINOL-derived chiral phosphoric acid as a catalyst to successfully achieve C2 asymmetric Fu-Ke alkylation reaction of C3 substituted fluorene with b, g-unsaturated-a-ketoimidate, high enantioselectivity A series of phosphonium C2 functionalized photoactive compounds have been synthesized. More importantly, the reaction products can be derivatized to synthesize a series of non-natural a-amino acid compounds containing quinone structures, which have important implications for organic synthesis chemistry and medicinal chemistry.
The study was funded by the National Natural Science Foundation of China (21102145) and Guangzhou Science and Technology Bureau's "Pearl River Science and Technology Rising Star" (2012J2200014).
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