Chapter 22, Problem 71PP

(a)

Interpretation Introduction

Interpretation:

The aldol condensation product for the given molecule should be identified.

Concept introduction:

Aldol condensation reaction is where the aldol addition product undergoes dehydration to give a conjugated enone. In organic chemistry condensation reaction means loss of small molecules. For aldol condensation reaction to take place the starting material should have two $\alpha$ hydrogens in the same carbon atom. The driving force for aldol condensation reaction is the formation of conjugated system. The steps involved in aldol condensation reaction are,

• Deprotonation of $\alpha$ carbon
• Attach of enolate ion with the aldehyde (nucleophilic attack)
• Protonation of the alkoxide ion to give aldol product
• Dehydration of the aldol addition product to form conjugated enone (aldol condensation product)

Please note that aldol condensation product is formed at higher temperature.

Note: Simple way to enter aldol condensation product is to remove the two $\alpha$ hydrogens from one carbonyl molecule and oxygen from another carbonyl molecule.  Form a double bond between the carbon atoms as shown in scheme below,

To draw : The aldol condensation product formed when the given compound (ketone) is heated in presence of base.

(b)

Interpretation Introduction

Interpretation:

The aldol condensation product for the given molecule should be identified.

Concept introduction:

Aldol condensation reaction is where the aldol addition product undergoes dehydration to give a conjugated enone. In organic chemistry condensation reaction means loss of small molecules. For aldol condensation reaction to take place the starting material should have two $\alpha$ hydrogens in the same carbon atom. The driving force for aldol condensation reaction is the formation of conjugated system. The steps involved in aldol condensation reaction are,

• Deprotonation of $\alpha$ carbon
• Attach of enolate ion with the aldehyde (nucleophilic attack)
• Protonation of the alkoxide ion to give aldol product
• Dehydration of the aldol addition product to form conjugated enone (aldol condensation product)

Please note that aldol condensation product is formed at higher temperature.

Note: Simple way to enter aldol condensation product is to remove the two $\alpha$ hydrogens from one carbonyl molecule and oxygen from another carbonyl molecule.  Form a double bond between the carbon atoms as shown in scheme below,

To draw : The aldol condensation product formed when the given compound (aldehyde) is heated in presence of base.

(c)

Interpretation Introduction

Interpretation:

The aldol condensation product for the given molecule should be identified.

Concept introduction:

Aldol condensation reaction is where the aldol addition product undergoes dehydration to give a conjugated enone. In organic chemistry condensation reaction means loss of small molecules. For aldol condensation reaction to take place the starting material should have two $\alpha$ hydrogens in the same carbon atom. The driving force for aldol condensation reaction is the formation of conjugated system. The steps involved in aldol condensation reaction are,

• Deprotonation of $\alpha$ carbon
• Attach of enolate ion with the aldehyde (nucleophilic attack)
• Protonation of the alkoxide ion to give aldol product
• Dehydration of the aldol addition product to form conjugated enone (aldol condensation product)

Please note that aldol condensation product is formed at higher temperature.

Note: Simple way to enter aldol condensation product is to remove the two $\alpha$ hydrogens from one carbonyl molecule and oxygen from another carbonyl molecule.  Form a double bond between the carbon atoms as shown in scheme below,

To draw : The aldol condensation product formed when the compound given aldehyde is heated in presence of base.