Aldehydes, Ketones And Carboxylic Acids

- Are you feeling tough? Let's make it extremely simple.
1
Remembering Name Reactions in One Go!
Lots of name reactions in this chapter, coupled with the name reactions of others chapters, and the result is confusion! For sure, it is tough to remember name reactions if you don't use a visual aid.
There are 10 name reactions in this chapter that can be divided into four types:
  1. Preparation of aldehydes and ketones
  2. Preparation of carboxylic acids
  3. Reactions of aldehydes and ketones
  4. Reactions of carboxylic acids
Now, you need to remember that there are four name reactions in preparation of aldehydes and ketones. By learning their reagents and what exactly is happening in the reaction, you will not get confused among the reactions.
Similarly, there's 1 name reaction in preparation of ketones, 3 in reactions of aldehydes and ketones, and 2 in reactions of carboxylic acids. Doing a comparative study of the reactions will help you learn them better, allowing a better recall during exam. Use this image as a visual aid:
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2

Acidity of Carboxylic Acids, No More Confusion There!

Acidity of carboxylic acids can be tough to learn because there are many factors that affect it. With many questions being asked for this concept, it's essential to master this.
The acidic nature of carboxylic acids is because of the formation of a stable carboxylate ion when carboxylic acids dissociate in water. The acidic nature of carboxylic acids is affected by a number of substituents like electron-withdrawing groups and electron-donating groups. Even the distance between substituents and the -COOH functional group affect the acidity of carboxylic acids. Here's a quick guide to remember acidic strength of carboxylic acids:
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3
Carboxylic Acids Do Not Undergo Nucleophilic Addition Reactions. But why?!
Aldehydes and ketones give nucleophilic addition reactions because of the presence of carbonyl functional (C=O) group. But then, carboxylic acids too possess a C=O group in its structure. Then why don't they undergo nucleophilic addition reactions? Well, the answer lies in the details. It's a little tough to crack, but if you understand the difference between the carbonyl carbon of aldehydes/ketones and that of carboxylic acids, you will have your answer.
The carbonyl group of aldehydes and ketones is polarised. So, it undergoes nucleophilic attack at the partial positive carbon. But, in carboxylic acids, the partial positive nature of the carbon of the carbonyl group is reduced due to resonance. So, it is not susceptible to nucleophilic addition.
But, carboxylic acids undergo nucleophilic substitution reactions where the nucleophile (-OH) is substituted by another nucleophile (Nu).
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