Predict the product(s) that would result when the following molecules are allowed to react under the following conditions: (i) 1. BH 3 2. NaOH, H 2 O 2 (ii) 1. Hg(OAc) 2 2. NaBH 4 (iii) H 2 SO 4 , H 2 O (iv) 1. OsO 4 2. NaHSO 3 (v) H 2 O (vi) NaOH, H 2 O . If there is no reaction, write 'no reaction.' (d)

Hello everyone. Today we have the following problem. What is the product of the following reaction under the specified conditions? Right? No reaction if there is no reaction. So here we have an alkene reacting with boron tetro fin sodium hydroxide and peroxide. This is hydro operation oxidation a reaction that installs a hydrox group at the least substituted position of the alkene. So when we go to draw our product, we will draw our carbon skeleton and on the more substituted carbon will be a proton and on the least substituted side of the carbon will be a hydroxyl group. And so that is because when we have our first step of this reaction, which is the sin addition of Bora to the alkene, we have the alkene that is attracted to the electron deficient boron from a nuclear attack on the boron. And then hydrogen is more electron negative than boron. So it will perform a simultaneous attack on the opposite side of the alkene. And so why that position? Well, that is because in this process, there's a partial positive charge that develops on the more substituted side of the alkene and the hydrogen is electron negative so it is going to prefer that portion more. And so with that, we have the product of this reaction overall, I hope it's helped. And until next time.

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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

10. Addition Reactions

Hydroboration

Organic Chemistry

10. Addition Reactions

Hydroboration

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Problem 88d

Textbook Question

Predict the product(s) that would result when the following molecules are allowed to react under the following conditions: (i) 1. BH₃ 2. NaOH, H₂O₂ (ii) 1. Hg(OAc)₂ 2. NaBH₄ (iii) H₂SO₄ , H₂O (iv) 1. OsO₄ 2. NaHSO₃ (v) H₂O (vi) NaOH, H₂O . If there is no reaction, write 'no reaction.'
(d)

Verified step by step guidance

Step 1: Analyze the given reaction conditions for each case. Each set of reagents corresponds to a specific organic reaction mechanism. For example, (i) involves hydroboration-oxidation, (ii) involves oxymercuration-demercuration, (iii) involves acid-catalyzed hydration, (iv) involves syn-dihydroxylation, (v) involves simple hydration, and (vi) involves basic hydrolysis.

Step 2: For (i) 1. BH₃ 2. NaOH, H₂O₂: This is a hydroboration-oxidation reaction. It adds water (H and OH) across a double bond in an anti-Markovnikov fashion, with syn addition. Identify the double bond in the molecule and predict the product by adding H to the more substituted carbon and OH to the less substituted carbon.

Step 3: For (ii) 1. Hg(OAc)₂ 2. NaBH₄: This is an oxymercuration-demercuration reaction. It adds water (H and OH) across a double bond in a Markovnikov fashion, without carbocation rearrangement. Locate the double bond in the molecule and predict the product by adding OH to the more substituted carbon and H to the less substituted carbon.

Step 4: For (iii) H₂SO₄, H₂O: This is an acid-catalyzed hydration reaction. It adds water (H and OH) across a double bond in a Markovnikov fashion, but carbocation rearrangement is possible. Identify the double bond, consider possible rearrangements, and predict the product by adding OH to the more substituted carbon and H to the less substituted carbon.

Step 5: For (iv) 1. OsO₄ 2. NaHSO₃: This is a syn-dihydroxylation reaction. It adds two hydroxyl groups (OH and OH) across a double bond in a syn fashion. Locate the double bond in the molecule and predict the product by adding OH groups to both carbons of the double bond on the same side of the molecule.

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Key Concepts

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

Hydroboration-Oxidation

Hydroboration-oxidation is a two-step reaction that converts alkenes into alcohols. In the first step, BH₃ adds to the double bond of the alkene, forming a trialkylborane intermediate. The second step involves oxidation with H₂O₂ and NaOH, which replaces the boron with a hydroxyl group, yielding an alcohol. This reaction is notable for its anti-Markovnikov selectivity.

Oxymercuration-Demercuration

Oxymercuration-demercuration is a method for converting alkenes to alcohols via mercuric acetate. The alkene reacts with Hg(OAc)₂ to form a mercurial intermediate, which is then reduced by NaBH₄ to yield an alcohol. This reaction follows Markovnikov's rule, where the hydroxyl group attaches to the more substituted carbon of the alkene.

Sulfation and Hydration Reactions

Sulfation and hydration reactions involve the addition of sulfuric acid (H₂SO₄) and water (H₂O) to alkenes. The alkene reacts with H₂SO₄ to form an alkyl sulfate, which can then be hydrolyzed to produce an alcohol. This reaction also adheres to Markovnikov's rule, leading to the formation of more stable carbocation intermediates.

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Predict the product(s) that would result when the following molecules are allowed to react under the following conditions: (i) 1. BH3 2. NaOH, H2O2 (ii) 1. Hg(OAc)2 2. NaBH4 (iii) H2SO4 , H2O (iv) 1. OsO4 2. NaHSO3 (v) H2O (vi) NaOH, H2O . If there is no reaction, write 'no reaction.'(d)

Key Concepts

Hydroboration-Oxidation

Oxymercuration-Demercuration

Sulfation and Hydration Reactions

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