Organic and biochemistry Assistance Lecturer Amjad Ahmed Jumaa  Nomenclature of the aldehydes and ketones  Reactions of the carbonyl compounds  Esters. 1

1-Nomenclature of aldehydes and ketones: Aldehydes: 1-Common names: Are derived from the names of the corresponding carboxylic acids by replacing – Ic of the acids by – aldehyde. 2- IUPAC nomenclature: Follow the usual pattern, the longest chain carrying the – CHO group is considered the parent structure and is named by replacing the – e of the corresponding alkane by – al. the position of a substituent is indicated by a number, the carbonyl carbon always being considered as C-1. In the common name the (alpha) is corresponding to C-2 in the IUPAC name. Look at the following examples: 1-Nomenclature of aldehydes and ketones: Aldehydes: 1-Common names: Are derived from the names of the corresponding carboxylic acids by replacing – Ic of the acids by – aldehyde. 2- IUPAC nomenclature: Follow the usual pattern, the longest chain carrying the – CHO group is considered the parent structure and is named by replacing the – e of the corresponding alkane by – al. the position of a substituent is indicated by a number, the carbonyl carbon always being considered as C-1. In the common name the (alpha) is corresponding to C-2 in the IUPAC name. Look at the following examples:

Ketones: A ketone in which the carbonyl group is attached to a benzene ring is named as a – phenone, as illustrated below. the longest chain carrying the carbonyl group is considered the parent structure, and is named by replacing the – e of the corresponding alkane with – one. The positions of various groups are indicated by numbers, the carbonyl carbon being given the lowest possible number. Ketones: A ketone in which the carbonyl group is attached to a benzene ring is named as a – phenone, as illustrated below. the longest chain carrying the carbonyl group is considered the parent structure, and is named by replacing the – e of the corresponding alkane with – one. The positions of various groups are indicated by numbers, the carbonyl carbon being given the lowest possible number.

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Problem: give the structure for the following ketones and aldehydes. 1-benzaldehyde. 2-(2-phenylbutanedial) 3-(benzylethylketone) 4-ethyl propyl ketone. Solution:

Follow problem: determine the structures for the following aldehydes and ketones. 1-(dibenzylketone) 2-(benzophenone) 3-(5-hydroxybentanal) 4-(1-phenyl-1- pentanol Follow problem: determine the structures for the following aldehydes and ketones. 1-(dibenzylketone) 2-(benzophenone) 3-(5-hydroxybentanal) 4-(1-phenyl-1- pentanol Reactions of carbonyl compounds: the carbonyl group, C=O, governs the chemistry of aldehydes and ketones. It does this in two ways: (a) By providing a site for nucleophilic addition, and (b) By increasing the acidity of the hydrogen atoms attached to the alpha carbon. Reactions of carbonyl compounds: the carbonyl group, C=O, governs the chemistry of aldehydes and ketones. It does this in two ways: (a) By providing a site for nucleophilic addition, and (b) By increasing the acidity of the hydrogen atoms attached to the alpha carbon.

8 The typical reaction of aldehydes and ketones is nucleophilic addition reaction. 1-oxidation. Just for aldehydes.

Problem: write the structure and the name for the oxidation of furfural in the presence of K 2 Cr 2 O 7, H 2 SO 4, and H 2 O? Solution : Follow problem: predict the name and the structure for the resulting carboxylic acid form oxidation of the following aldehydes by using (K 2 Cr 2 O 7, H 2 SO 4, H 2 O). 1-heptanal. 2-benzaldehyde 3-(para-tolualdehyde) 4-phenylacetaldehyde 5-formaldehyde.

2-addition of derivatives of ammonia. For both aldehydes and ketones.

11 Example: Problem: give balanced equation for the following reaction in the acidic medium: 1-heptanal with hydroxylamine.

Solution: Esters: Closely related to the carboxylic acid and to each other are a number of chemical families known as functional derivatives of carboxylic acid. These derivatives are compounds in which the hydroxyl group – OH has been replaced by – OR' group. The general formula of the esters is: Esters: Closely related to the carboxylic acid and to each other are a number of chemical families known as functional derivatives of carboxylic acid. These derivatives are compounds in which the hydroxyl group – OH has been replaced by – OR' group. The general formula of the esters is: