Cage-Shaped Borate Catalysts Bearing Precisely Controlled Lewis Acidity and Their Application in Glycosylations
Yoshiyuki Manabe1,2, Yuya Tsutsui3, Yosuke Tanaka1
1Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan.
Abstract:
Cage-shaped borates, whose Lewis acidity can be precisely modulated by the structural attributes of the triphenolic ligands, were employed as catalysts for glycosylation. Each cage-shaped borate displayed distinctive reactivity; thus, screening of the borate catalysts enabled controllable activation of glycosyl fluorides under mild conditions. Practical glycosylation was achieved by fine-tuning the Lewis acidity tailored to the substrate reactivity, thereby providing a versatile method applicable to the synthesis of complex glycans.
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