Chapter 11.SE, Problem 58AP

Interpretation Introduction

a) NaBH₄ and H₃O⁺

Interpretation:

The products produced when 1) phenylacetaldehyde and 2) acetophenone are treated first with NaBH₄ and then with H₃O⁺ are to be given.

Concept introduction:

NaBH₄, either in water or in alcohol reduce aldehydes to primary alcohols and ketones to a secondary alcohol.

To give:

The products produced when 1) phenylacetaldehyde and 2) acetophenone are treated first with NaBH₄ and then with H₃O⁺.

Answer to Problem 58AP

The product produced when 1) phenylacetaldehyde is treated first with NaBH₄ and then with H₃O⁺ is 2-phenylethanol.

The product produced when acetophenone is treated first with NaBH₄ and then with H₃O⁺ is 1-phenylethanol.

Explanation of Solution

Phenylacetaldehyde, being an aldehyde is reduced by NaBH₄ to a primary alcohol, 2-phenylethanol.

Acetophenone, being a ketone is reduced by NaBH₄ to a secondary alcohol, 1-phenylethanol.

Conclusion

The product produced when 1) phenylacetaldehyde is treated first with NaBH₄ and then with H₃O⁺ is 2-phenylethanol.

The product produced when acetophenone is treated first with NaBH₄ and then with H₃O⁺ is 1-phenylethanol.

Interpretation Introduction

b) Dess-Martin reagent

Interpretation:

The products produced when 1) phenylacetaldehyde and 2) acetophenone are treated with Dess-Martin reagent are to be given.

Concept introduction:

Aldehydes and ketones are not oxidized by Dess-Martin reagent.

To give:

The products produced when 1) phenylacetaldehyde and 2) acetophenone are treated with Dess-Martin reagent.

Answer to Problem 58AP

Phenylacetaldehyde does not react with Dess-Martin reagent.

Acetophenone does not react with Dess-Martin reagent.

Explanation of Solution

Aldehydes and ketones are not oxidized by Dess-Martin reagent.

Conclusion

Phenylacetaldehyde does not react with Dess-Martin reagent.

Acetophenone does not react with Dess-Martin reagent.

Interpretation Introduction

c) NH₂OH, HCl catalyst

Interpretation:

The products produced when 1) phenylacetaldehyde and 2) acetophenone are treated with NH₂OH in the presence of HCl catalyst are to be given.

Concept introduction:

Aldehydes and ketones react with hydroxyl amne in the presence of an acid catalyst to yield aloximes and ketoximes respectively.

To give:

The products produced when 1) phenylacetaldehyde and 2) acetophenone are treated with NH₂OH in the presence of HCl catalyst.

Answer to Problem 58AP

The product produced when phenylacetaldehyde is treated with NH₂OH in the presence of HCl catalyst is

The product produced when acetophenone is treated with NH₂OH in the presence of HCl catalyst is

Explanation of Solution

phenylacetaldehyde reacts with NH₂OH in the presence of HCl catalystto yield phenylacetaldoxime.

Acetophenone reacts with NH₂OH in the presence of HCl catalyst to give acetophenoneoxime.

Conclusion

The product produced when phenylacetaldehyde is treated with NH₂OH in the presence of HCl catalyst is

The product produced when acetophenone is treated with NH₂OH in the presence of HCl catalyst is

Interpretation Introduction

d) CH₃MgBr and H₃O⁺

Interpretation:

The products produced when 1) phenylacetaldehyde and 2) acetophenone are treated first with CH₃MgBr and then with H₃O⁺ are to be given.

Concept introduction:

On treatment with Grignard reagents followed by acidification, aldehydes other than formaldehyde yield secondary alcohols and ketones give tertiary alcohols.

To give:

The products produced when 1) phenylacetaldehyde and 2) acetophenone are treated first with CH₃MgBr and then with H₃O⁺.

Answer to Problem 58AP

The product produced when phenylacetaldehyde is treated first with CH₃MgBr and then with H₃O⁺ is

The products produced when acetophenone is treated first with CH₃MgBr and then with H₃O⁺ is

Explanation of Solution

When phenylacetaldehyde is treated first with CH₃MgBr and then with H₃O⁺ the product produced is 1-phenyl-2-propanol, a secondary alcohol.

When acetophenone is treated first with CH₃MgBr and then with H₃O⁺ the product produced is 2-phenyl-2-propanol, a tertiary alcohol.

Conclusion

The product produced when phenylacetaldehyde is treated first with CH₃MgBr and then with H₃O⁺ is

The products produced when acetophenone is treated first with CH₃MgBr and then with H₃O⁺ is

Interpretation Introduction

e) CH₃OH, HCl catalyst

Interpretation:

The products produced when 1) phenylacetaldehyde and 2) acetophenone are treated with two equivalents of CH₃OH in the presence of HCl catalyst are to be given.

Concept introduction:

Aldehydes react reversibley with two equivalents of an alcohol in the presence of an acid catalyst to yield acetals and ketones react to give ketals.

To give:

The product produced when phenylacetaldehyde is treated with two equivalents of CH₃OH in the presence of HCl catalyst.

Answer to Problem 58AP

The product produced when phenylacetaldehyde is treated with two equivalents of CH₃OH in the presence of HCl catalyst is

The product produced when acetophenone is treated with two equivalents of CH₃OH in the presence of HCl catalyst is

Explanation of Solution

Phenylacetaldehyde reacts with two equivalents of CH₃OH in the presence of HCl catalyst to yield an acetal.

Acetophenone reacts with two equivalents of CH₃OH in the presence of HCl catalyst to yield a ketal.

Conclusion

The product produced when phenylacetaldehyde is treated with two equivalents of CH₃OH in the presence of HCl catalyst is

The product produced when acetophenone is treated with two equivalents of CH₃OH in the presence of HCl catalyst is

Interpretation Introduction

f) NH₂NH₂, KOH

Interpretation:

The product produced when 1) phenylacetaldehyde and 2) acetophenone are treated with NH₂NH₂ in the presence of KOH are to be given.

Concept introduction:

The aldehydes and ketones undergo Wolff-Kishner reduction to yield alkanes when treated with NH₂NH₂ in the presence of KOH. The –CHO of aldehydes is reduced to –CH₃ and C=O in ketone also is reduced to –CH₂.

To give:

The product produced when 1) phenylacetaldehyde and 2) acetophenone are treated first with NH₂NH₂ and KOH.

Answer to Problem 58AP

The product produced when phenylacetaldehyde is treated with NH₂NH₂ and KOH is

The product produced when acetophenone is treated with NH₂NH₂ and KOH is

Explanation of Solution

Phenylacetaldehyde is reduced by NH₂NH₂ and KOH to ethylbenzene.

Acetophenone also is reduced by NH₂NH₂ and KOH to ethylbenzene.

Conclusion

The product produced when phenylacetaldehyde is treated with NH₂NH₂ and KOH is

The product produced when acetophenone is treated with NH₂NH₂ and KOH is

Interpretation Introduction

g) (C₆H₅)₃P=CH₂

Interpretation:

The products produced when 1) phenylacetaldehyde and 2) acetophenone are treated with (C₆H₅)₃P=CH₂ are to be given.

Concept introduction:

The reaction given is Wittig reaction. Aldehydes and ketones are converted into alkenes. In this reaction, a triphenylphosphorus ylide adds to aldehydes and ketones to yield alkenes.

To give:

The products produced when 1) phenylacetaldehyde and 2) acetophenone are treated with (C₆H₅)₃P=CH₂.

Answer to Problem 58AP

The product produced when phenylacetaldehyde is treated with (C₆H₅)₃P=CH₂ is

The product produced when acetophenone are treated with (C₆H₅)₃P=CH₂ is

Explanation of Solution

Phenylacetaldehyde reacts with with (C₆H₅)₃P=CH₂ to yield 3-phenylpropene.

Acetophenone reacts with with (C₆H₅)₃P=CH₂ to yield 2-phenylpropene.

Conclusion

The product produced when phenylacetaldehyde is treated with (C₆H₅)₃P=CH₂ is

The product produced when acetophenone are treated with (C₆H₅)₃P=CH₂ is

Interpretation Introduction

h) HCN, KCN

Interpretation:

The products produced when 1) phenylacetaldehyde and 2) acetophenone are treated with HCN, KCN are to be given.

Concept introduction:

Aldehydes and ketones undergo nucleophilic addition reaction.

To give:

The products produced when 1) phenylacetaldehyde and 2) acetophenone are treated first with HCN, KCN to yield their cyanohydrins.

Answer to Problem 58AP

The product produced when phenylacetaldehyde is treated with HCN, KCN is

The products produced when acetophenone is treated with HCN, KCN is

Explanation of Solution

When phenylacetaldehyde is treated with HCN, KCN, it gives phenylacetaldehydecyanohydrin.

When acetophenone is treated with HCN, KCN, it gives acetophenonecyanohydrin.

Conclusion

The product produced when phenylacetaldehyde is treated with HCN, KCN is

The products produced when acetophenone is treated with HCN, KCN is