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Koenigs-Knorr Glycosylation Reaction Catalyzed by Trimethylsilyl Trifluoromethanesulfonate.

ABSTRACT: The discovery that traditional silver(I)-oxide-promoted glycosidations of glycosyl bromides (Koenigs-Knorr reaction) can be greatly accelerated in the presence of catalytic trimethylsilyl trifluoromethanesulfonate (TMSOTf) is reported. The reaction conditions are very mild that allowed for maintaining a practically neutral pH and, at the same time, providing high rates and excellent glycosylation yields. In addition, unusual reactivity trends among a series of differentially protected glycosyl bromides were documented. In particular, benzoylated ?-bromides were much more reactive than their benzylated counterparts under these conditions.

SUBMITTER: Singh Y

PROVIDER: S-EPMC6522226 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Koenigs-Knorr Glycosylation Reaction Catalyzed by Trimethylsilyl Trifluoromethanesulfonate.

Singh Yashapal Y Demchenko Alexei V AV

Chemistry (Weinheim an der Bergstrasse, Germany) 20181220 6

The discovery that traditional silver(I)-oxide-promoted glycosidations of glycosyl bromides (Koenigs-Knorr reaction) can be greatly accelerated in the presence of catalytic trimethylsilyl trifluoromethanesulfonate (TMSOTf) is reported. The reaction conditions are very mild that allowed for maintaining a practically neutral pH and, at the same time, providing high rates and excellent glycosylation yields. In addition, unusual reactivity trends among a series of differentially protected glycosyl b ...[more]

PMID: 30407673

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