Table of contents

1. A Review of General Chemistry5h 5m
2. Molecular Representations1h 14m
3. Acids and Bases2h 46m
4. Alkanes and Cycloalkanes4h 17m
5. Chirality3h 39m
6. Thermodynamics and Kinetics1h 22m
7. Substitution Reactions1h 48m
8. Elimination Reactions2h 30m
9. Alkenes and Alkynes2h 9m
10. Addition Reactions3h 19m
11. Radical Reactions1h 58m
12. Alcohols, Ethers, Epoxides and Thiols2h 42m
13. Alcohols and Carbonyl Compounds2h 17m
14. Synthetic Techniques1h 26m
15. Analytical Techniques:IR, NMR, Mass Spect7h 3m
16. Conjugated Systems6h 13m
17. Ultraviolet Spectroscopy51m
18. Aromaticity2h 34m
19. Reactions of Aromatics: EAS and Beyond5h 1m
20. Phenols55m
21. Aldehydes and Ketones: Nucleophilic Addition4h 56m
22. Carboxylic Acid Derivatives: NAS2h 51m
23. The Chemistry of Thioesters, Phophate Ester and Phosphate Anhydrides1h 10m
24. Enolate Chemistry: Reactions at the Alpha-Carbon1h 53m
25. Condensation Chemistry2h 9m
26. Amines1h 43m
27. Heterocycles2h 0m
28. Carbohydrates5h 53m
29. Amino Acids4h 20m
30. Peptides and Proteins2h 42m
31. Catalysis in Organic Reactions1h 30m
32. Lipids 2h 50m
33. The Organic Chemistry of Metabolic Pathways2h 52m
34. Nucleic Acids1h 32m
35. Transition Metals6h 14m
36. Synthetic Polymers1h 49m

28. Carbohydrates

Monosaccharides - Forming Cyclic Hemiacetals

Organic Chemistry

28. Carbohydrates

Monosaccharides - Forming Cyclic Hemiacetals

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Multiple Choice

In the formation of a cyclic hemiacetal from a monosaccharide, what type of reaction occurs?

Condensation reaction

Hydrolysis reaction

Intramolecular nucleophilic addition

Oxidation reaction

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Verified step by step guidance

Understand the structure of a monosaccharide: Monosaccharides are simple sugars that contain an aldehyde or ketone group and multiple hydroxyl groups. In the context of forming a cyclic hemiacetal, focus on the aldehyde group and the hydroxyl group that will participate in the reaction.

Identify the functional groups involved: In a monosaccharide, the aldehyde group (or ketone group) can react with a hydroxyl group within the same molecule. This is an intramolecular reaction, meaning it occurs within a single molecule.

Recognize the type of reaction: The formation of a cyclic hemiacetal involves an intramolecular nucleophilic addition reaction. The hydroxyl group acts as a nucleophile, attacking the electrophilic carbonyl carbon of the aldehyde or ketone group.

Visualize the mechanism: The nucleophilic hydroxyl group donates a pair of electrons to the carbonyl carbon, forming a new covalent bond. This results in the opening of the carbonyl group and the formation of a new ring structure, which is the cyclic hemiacetal.

Consider the stereochemistry: The formation of a cyclic hemiacetal can lead to different stereoisomers, depending on the orientation of the hydroxyl group and the resulting ring structure. This is important in understanding the diversity of cyclic forms that monosaccharides can adopt.