A general approach to C-Acyl glycosides via palladium/copper Co-catalyzed coupling reaction of glycosyl carbothioates and arylboronic acids
作者:Li-Na Wang、You-Hong Niu、Qing-Hui Cai、Qin Li、Xin-Shan Ye
DOI:10.1016/j.tet.2021.131955
日期:2021.2
A general and efficient approach to the synthesis of various C-acyl glycosides has been developed via Pd2(dba)3/CuTC co-catalyzed cross-coupling reaction of glycosyl carbothioates with arylboronic acids. The reaction showed a broad substrate scope and 25 examples were exhibited in 61%–97% isolated yields. Furthermore, this reaction was applied to the gram-scale preparation of C-acyl glycosides. The
deoxygenation, were subjected to a one-pot reaction sequence involving N-methylation of the heterocyclic ring by MeOTf, treatment of the N-methylbenzothiazolium salt with a Grignard reagent, and HgCl2-promoted hydrolysis of the benzothiazoline thus formed. The resulting ketones were isolated in yields varying from 35 to 80%. Treatment of the sugar ketones with various organometals containing the phenyl