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 - Weak Oxidation (Aldonic Acid)

Organic Chemistry

28. Carbohydrates

Monosaccharides - Weak Oxidation (Aldonic Acid)

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2:51 minutes

Problem 34e

Textbook Question

What product or products are obtained when D-galactose reacts with each of the following?
e. Br₂ in water

Verified step by step guidance

Identify the functional groups present in d-galactose. D-galactose is an aldose sugar, meaning it contains an aldehyde group (-CHO) at the anomeric carbon (C1) and hydroxyl groups (-OH) on the other carbons.

Understand the reactivity of Br2 in water. Bromine in water is a mild oxidizing agent that selectively oxidizes aldehydes to carboxylic acids without affecting other functional groups like alcohols.

Focus on the aldehyde group in d-galactose. The aldehyde group at C1 will be oxidized to a carboxylic acid group (-COOH), converting d-galactose into d-galactonic acid.

Note that the hydroxyl groups on the other carbons of d-galactose remain unchanged during this reaction because Br2 in water does not oxidize alcohols under these conditions.

Conclude that the product of the reaction is d-galactonic acid, which is the oxidized form of d-galactose where the aldehyde group has been converted to a carboxylic acid group.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Oxidation of Sugars

The reaction of sugars like d-galactose with oxidizing agents, such as Br2 in water, leads to the oxidation of the hydroxyl groups. This process can convert the aldehyde or alcohol functional groups into carboxylic acids or other oxidized forms, depending on the conditions and the specific sugar structure.

D-Galactose Structure

D-galactose is a six-carbon aldose sugar with a specific stereochemistry. Understanding its structure, including the arrangement of hydroxyl groups and the aldehyde functional group, is crucial for predicting the products of its reactions, particularly how it interacts with oxidizing agents.

Halogenation Reactions

Halogenation involves the introduction of halogen atoms into organic compounds. In the case of d-galactose reacting with Br2 in water, the reaction can lead to the formation of brominated products, which may include oxidized forms of the sugar, highlighting the importance of understanding reaction mechanisms in organic chemistry.

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