Interpretation:
Using curved arrows, a mechanism is to be written to show the formation of oxygen-stabilized carbocation from each of the glycosyl donor.
Concept introduction:
The sulfide acts as a good nucleophile on reaction with an electrophile and forms sulfonium salts.
In pyranose, the carbocation formed at anomeric carbon stabilized by delocalization of pi electrons on oxygen is called oxygen-stabilized carbocation.
Due to planarity, the group attacking the oxygen-stabilized carbocation may approach from either side of the ring and gives
Trimethylsilyl trifluoromethanesulfonate or methyl trifluoromethanesulfonate can be used to convert the group or atom to a good leaving group in a substitution reaction.
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Organic Chemistry - Standalone book
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- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning