Niklas Henrik Fischer, Alicja Klaudia Bałuta, Maciej Tadeusz Szpak, Peter Waaben Thulstrup and Christian Marcus Pedersen
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引用次数: 0
Abstract
We report the UV-mediated activation of various glycosyl α-trichloroacetimidates (TCAs) to form glycosyl α-chlorides or O-glycosides depending on the carbohydrate, protecting groups, and solvent. In THF, Et2O, and CH2Cl2, most of the glycosyl TCAs studied underwent conversion to their respective α-chlorides. In the case of per-acetylated glucosyl TCA, a reaction with THF was observed which caused formation of the 4′-chlorobutyl β-glucoside. O-Glycosylation with primary and secondary alcohols present in large excess was found to take place in acetonitrile, which was chosen as solvent because it does not facilitate competing glycosyl chloride formation. Fluorescent byproducts were formed in THF, Et2O, and in reactions with benzyl-protected TCAs. We propose that this is a result of decomposition of 2,3-dichloromaleimide formed from eliminated trichloroacetamide via a series of radical reactions.
期刊介绍:
Organic & Biomolecular Chemistry is an international journal using integrated research in chemistry-organic chemistry. Founded in 2003 by the Royal Society of Chemistry, the journal is published in Semimonthly issues and has been indexed by SCIE, a leading international database. The journal focuses on the key research and cutting-edge progress in the field of chemistry-organic chemistry, publishes and reports the research results in this field in a timely manner, and is committed to becoming a window and platform for rapid academic exchanges among peers in this field. The journal's impact factor in 2023 is 2.9, and its CiteScore is 5.5.