
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.

Want to see the full answer?
Check out a sample textbook solution
Chapter 24 Solutions
ORGANIC CHEMISTRY (LOOSELEAF)-PACKAGE
- Determine if the following salt is neutral, acidic or basic. If acidic or basic, write the appropriate equilibrium equation for the acid or base that exists when the salt is dissolved in aqueous solution. If neutral, simply write only NR. Be sure to include the proper phases for all species within the reaction LiNO3arrow_forwardAn unknown weak acid with a concentration of 0.410 M has a pH of 5.600. What is the Ka of the weak acid?arrow_forward(racemic) 19.84 Using your reaction roadmaps as a guide, show how to convert 2-oxepanone and ethanol into 1-cyclopentenecarbaldehyde. You must use 2-oxepanone as the source of all carbon atoms in the target molecule. Show all reagents and all molecules synthesized along the way. & + EtOH H 2-Oxepanone 1-Cyclopentenecarbaldehydearrow_forward
- R₂ R₁ R₁ a R Rg Nu R₂ Rg R₁ R R₁₂ R3 R R Nu enolate forming R₁ R B-Alkylated carbonyl species or amines Cyclic B-Ketoester R₁₁ HOB R R₁B R R₁₂ B-Hydroxy carbonyl R diester R2 R3 R₁ RB OR R₂ 0 aB-Unsaturated carbonyl NaOR Aldol HOR reaction 1) LDA 2) R-X 3) H₂O/H₂O ketone, aldehyde 1) 2°-amine 2) acid chloride 3) H₂O'/H₂O 0 O R₁ R₁ R R₁ R₁₂ Alkylated a-carbon R₁ H.C R₁ H.C Alkylated methyl ketone acetoacetic ester B-Ketoester ester R₁ HO R₂ R B-Dicarbonyl HO Alkylated carboxylic acid malonic ester Write the reagents required to bring about each reaction next to the arrows shown. Next, record any regiochemistry or stereochemistry considerations relevant to the reaction. You should also record any key aspects of the mechanism, such as forma- tion of an important intermediate, as a helpful reminder. You may want to keep track of all reactions that make carbon-carbon bonds, because these help you build large molecules from smaller fragments. This especially applies to the reactions in…arrow_forwardProvide the reasonable steps to achieve the following synthesis.arrow_forwardIdentify which compound is more acidic. Justify your choice.arrow_forward
- Provide the reasonable steps to achieve the following synthesis.arrow_forwardWhen anisole is treated with excess bromine, the reaction gives a product which shows two singlets in 1H NMR. Draw the product.arrow_forward(ii) Draw a reasonable mechanism for the following reaction: CI NaOH heat OH (hint: SNAr Reaction) :arrow_forward
- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage LearningIntroduction to General, Organic and BiochemistryChemistryISBN:9781285869759Author:Frederick A. Bettelheim, William H. Brown, Mary K. Campbell, Shawn O. Farrell, Omar TorresPublisher:Cengage LearningChemistry for Today: General, Organic, and Bioche...ChemistryISBN:9781305960060Author:Spencer L. Seager, Michael R. Slabaugh, Maren S. HansenPublisher:Cengage Learning



