The structural formula for the betaine formed by the reaction of methylenetriphenylphosphorane with cyclohexanone is to be drawn. The conversion of the betaine to an oxaphosphetane is to be shown using curved arrows. Also, the one-step conversion of the betaine to methylenecyclohexane and triphenylphosphine oxide is to be shown using curved arrows. Concept introduction: The reaction of an aldehyde or a ketone with triphenylphosphonium ylide results in the formation of an alkene as the final product. This reaction is commonly known as Wittig reaction. In the first step of the reaction, the nucleophilic attack of the ylide on the carbonyl carbon takes place to form betaine. In the second step, the formation of the four-membered ring, oxaphosphetane occurs and in the final step, the alkene is formed as a product.

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Answer 1

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Definition Definition Organic compounds that have a carbonyl group, C=O, as their functional group. The carbonyl group in aldehydes is placed at the end of the molecular structure, which means the C=O is attached to one hydrogen atom and an alkyl group or a benzene ring. Just like all the other homologous series in organic chemistry, the naming of aldehydes uses the suffix “-al”. The general molecular formula is C n H 2n O.

Chapter 18.12, Problem 21P

Interpretation Introduction

Interpretation:

The structural formula for the betaine formed by the reaction of methylenetriphenylphosphorane with cyclohexanone is to be drawn. The conversion of the betaine to an oxaphosphetane is to be shown using curved arrows. Also, the one-step conversion of the betaine to methylenecyclohexane and triphenylphosphine oxide is to be shown using curved arrows.

Concept introduction:

The reaction of an aldehyde or a ketone with triphenylphosphonium ylide results in the formation of an alkene as the final product.

This reaction is commonly known as Wittig reaction.

In the first step of the reaction, the nucleophilic attack of the ylide on the carbonyl carbon takes place to form betaine.

In the second step, the formation of the four-membered ring, oxaphosphetane occurs and in the final step, the alkene is formed as a product.

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Answer 2

Question

Definition Definition Organic compounds that have a carbonyl group, C=O, as their functional group. The carbonyl group in aldehydes is placed at the end of the molecular structure, which means the C=O is attached to one hydrogen atom and an alkyl group or a benzene ring. Just like all the other homologous series in organic chemistry, the naming of aldehydes uses the suffix “-al”. The general molecular formula is C n H 2n O.

Chapter 18.12, Problem 21P

Interpretation Introduction

Interpretation:

The structural formula for the betaine formed by the reaction of methylenetriphenylphosphorane with cyclohexanone is to be drawn. The conversion of the betaine to an oxaphosphetane is to be shown using curved arrows. Also, the one-step conversion of the betaine to methylenecyclohexane and triphenylphosphine oxide is to be shown using curved arrows.

Concept introduction:

The reaction of an aldehyde or a ketone with triphenylphosphonium ylide results in the formation of an alkene as the final product.

This reaction is commonly known as Wittig reaction.

In the first step of the reaction, the nucleophilic attack of the ylide on the carbonyl carbon takes place to form betaine.

In the second step, the formation of the four-membered ring, oxaphosphetane occurs and in the final step, the alkene is formed as a product.

Expert Solution & Answer

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Answer 3

Question

Definition Definition Organic compounds that have a carbonyl group, C=O, as their functional group. The carbonyl group in aldehydes is placed at the end of the molecular structure, which means the C=O is attached to one hydrogen atom and an alkyl group or a benzene ring. Just like all the other homologous series in organic chemistry, the naming of aldehydes uses the suffix “-al”. The general molecular formula is C n H 2n O.

Chapter 18.12, Problem 21P

Interpretation Introduction

Interpretation:

The structural formula for the betaine formed by the reaction of methylenetriphenylphosphorane with cyclohexanone is to be drawn. The conversion of the betaine to an oxaphosphetane is to be shown using curved arrows. Also, the one-step conversion of the betaine to methylenecyclohexane and triphenylphosphine oxide is to be shown using curved arrows.

Concept introduction:

The reaction of an aldehyde or a ketone with triphenylphosphonium ylide results in the formation of an alkene as the final product.

This reaction is commonly known as Wittig reaction.

In the first step of the reaction, the nucleophilic attack of the ylide on the carbonyl carbon takes place to form betaine.

In the second step, the formation of the four-membered ring, oxaphosphetane occurs and in the final step, the alkene is formed as a product.

Expert Solution & Answer

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Check out a sample textbook solution

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Answer 4

Question

Definition Definition Organic compounds that have a carbonyl group, C=O, as their functional group. The carbonyl group in aldehydes is placed at the end of the molecular structure, which means the C=O is attached to one hydrogen atom and an alkyl group or a benzene ring. Just like all the other homologous series in organic chemistry, the naming of aldehydes uses the suffix “-al”. The general molecular formula is C n H 2n O.

Chapter 18.12, Problem 21P

Interpretation Introduction