936549-98-3Relevant academic research and scientific papers
Borinic Acid Catalyzed Stereo- and Regioselective Couplings of Glycosyl Methanesulfonates
D'Angelo, Kyan A.,Taylor, Mark S.
, p. 11058 - 11066 (2016)
In the presence of a diarylborinic acid catalyst, glycosyl methanesulfonates engage in regio- and stereoselective couplings with partially protected pyranoside and furanoside acceptors. The methanesulfonate donors are prepared in situ from glycosyl hemiacetals, and are coupled under mild, operationally simple conditions (amine base, organoboron catalyst, room temperature). The borinic acid catalyst not only influences site-selectivity via activation of 1,2- or 1,3-diol motifs, but also has a pronounced effect on the stereochemical outcome: 1,2-trans-linked disaccharides are obtained selectively in the absence of neighboring group participation. Reaction progress kinetic analysis was used to obtain insight into the mechanism of glycosylation, both in the presence of catalyst and in its absence, while rates of interconversion of methanesulfonate anomers were determined by NMR exchange spectroscopy (EXSY). Together, the results suggest that although the uncatalyzed and catalyzed reactions give rise to opposite stereochemical outcomes, both proceed by associative mechanisms.
Efficient and selective removal of chloroacetyl group promoted with tetra-n-butylammonium fluoride (TBAF)
Gu, Guofeng,Fang, Min,Du, Yuguo
experimental part, p. 2801 - 2804 (2012/01/02)
A practical method for the efficient and selective cleavage of chloroacetyl protecting group using tetra-n-butylammonium fluoride (TBAF) in THF solution at rt was disclosed.
