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Updated: Sep 13, 2025

Activation and Conjugation of Soluble Polysaccharides using 1-Cyano-4-Dimethylaminopyridine Tetrafluoroborate CDAP
Published on: June 14, 2021
Fluoride-Effect-Directed Catalyst-Controlled Regioselective Acylation of Carbohydrate Diols and Triols
Miaomiao Zhang1, Yue Yang1, Tong Li1
1National Glycoengineering Research Center, Shandong Technology Innovation Center of Carbohydrate, Shandong University, Qingdao 266237, P. R. China.
None:
Herein, we report that acyl fluorides enable the switchable selective acylation of vicinal 1,2-cis-diol motifs in carbohydrates. While DMAP as a catalyst directs equatorial acylation, DBU highly promotes the thermodynamically unfavorable axial O-acylation, reversing conventional preferences. NMR studies and DFT calculations indicate that triple hydrogen bonding governs this unusual regioselectivity. This method eliminates the need for metal salts, elaborate catalysts, or complex ligands, offering a practical and efficient platform for regioselective carbohydrate transformation and synthesis.
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