Question

Write names for the following carboxylic acids: (a) CC(C)C=CCC(=O)O (b) CC(C)C(N)C(=O)O (c) O=C(O)C1CC(O)C1 (d) O=C(O)c1cccc(O)c1 (e) CC(CC(=O)O)c1ccccc1 (f) C=C(C)C(CC(=O)O)c1ccccc1 (g) CC(CC(=O)O)C(Br)(Br)Br (h) NCC(O)C(=O)O

Short answer

a) 5-Methylhex-3-enoic acid, b) 2-Methyl-3-aminobutanoic acid, c) 3-Hydroxycyclopentanecarboxylic acid, d) 4-Hydroxybenzoic acid, e) 3-Phenylpropanoic acid, f) 4-Methyl-3-phenylbut-2-enoic acid, g) 2,2,2-Tribromobutanoic acid, h) 2-Aminoacetic acid

Step-by-step solution

Identify and Name the Parent Chain

For each structure, identify the longest carbon chain that includes the carboxyl group and name the parent hydrocarbon chain using the IUPAC guidelines.

Number the Carbon Atoms

Number the carbon atoms in the parent chain starting from the carboxyl carbon as 1. This ensures the carboxyl group gets the highest priority.

Identify and Name Substituents

Identify any substituents attached to the parent chain and assign numbers to their positions according to the IUPAC nomenclature rules.

Combine All Parts

Combine the names of the substituents with the name of the parent chain, including their position numbers, to get the full IUPAC name.

Part (a)

Structure: CC(C)C=CCC(=O)O Parent Chain: Hexenoic acid Substituents: 5-Methyl and 3,4-double bond IUPAC Name: 5-Methylhex-3-enoic acid

Part (b)

Structure: CC(C)C(N)C(=O)O Parent Chain: Butanoic acid Substituents: 3-Amino and 2-Methyl IUPAC Name: 2-Methyl-3-aminobutanoic acid

Part (c)

Structure: O=C(O)C1CC(O)C1 Parent Chain: Cyclopentanecarboxylic acid Substituents: 3-Hydroxy IUPAC Name: 3-Hydroxycyclopentanecarboxylic acid

Part (d)

Structure: O=C(O)c1cccc(O)c1 Parent Chain: Benzene carboxylic acid (benzoic acid) Substituents: 4-Hydroxy IUPAC Name: 4-Hydroxybenzoic acid

Part (e)

Structure: CC(CC(=O)O)c1ccccc1 Parent Chain: Phenylpropanoic acid Substituents: None IUPAC Name: 3-Phenylpropanoic acid

Part (f)

Structure: C=C(C)C(CC(=O)O)c1ccccc1 Parent Chain: Phenylbutenoic acid Substituents: 4-Methyl, 1,2-Double bond IUPAC Name: 4-Methyl-3-phenylbut-2-enoic acid

Part (g)

Structure: CC(CC(=O)O)C(Br)(Br)Br Parent Chain: Butanoic acid Substituents: 2,2,2-Tribromoethyl IUPAC Name: 2,2,2-Tribromobutanoic acid

Part (h)

Structure: NCC(O)C(=O)O Parent Chain: Glycine Substituents: None IUPAC Name: 2-Aminoacetic acid

Key concepts

IUPAC Naming

The IUPAC system is the International Union of Pure and Applied Chemistry's method to name organic compounds consistently and systematically. The goal is to ensure each compound has a unique name. To name a compound: identify the longest continuous carbon chain that includes the highest-priority functional group, number the chain starting from the end nearest the functional group, and name any substituents with their position numbers. Combine these parts to get the full name.

Organic Chemistry

Organic chemistry focuses on the study of carbon-containing compounds. Carboxylic acids are a key group in organic chemistry. They contain a carbon-oxygen double bond (carbonyl) and an -OH group (hydroxyl). Understanding the naming of carboxylic acids involves knowing the structure and properties of these compounds. Common tasks include predicting reactivity and naming compounds using IUPAC nomenclature rules.

Functional Groups

Functional groups are specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules. In carboxylic acids, the functional group is the carboxyl group (-COOH). This group has a double-bonded oxygen and a hydroxyl group attached to a carbon atom. Identifying functional groups is crucial for naming and predicting the behavior of organic compounds.

SMILES Notation

Simplified Molecular Input Line Entry System (SMILES) is a specification for describing the structure of chemical molecules using short ASCII strings. SMILES notations are used to input molecular structures into various chemical databases and software. For instance, CC(C)C=CCC(=O)O represents a molecule with a particular sequence of carbon atoms and functional groups.

Substituents

Substituents are atoms or groups of atoms attached to the carbon chain of an organic molecule in place of a hydrogen atom. In IUPAC naming, substituents are often prefixed to the name of the parent hydrocarbon chain along with their numerical position. For example, in 5-Methylhex-3-enoic acid, '5-Methyl' indicates a methyl group on the fifth carbon of the hexene chain.

Carbon Chains

Carbon chains form the backbone of organic molecules. Carboxylic acids are characterized by the -COOH group attached to a carbon chain. The length and structure of the carbon chain determine the name of the compound. For example, 'hex' in hexenoic acid indicates a six-carbon chain. Being familiar with these chains and their naming conventions is essential for understanding organic chemistry.