Question

Give the IUPAC and common names (if any) for each of the following amides: a. CC(N)=O b. CCCC(N)=O c. NC(=O)c1ccccc1

Short answer

a. Ethanamide (Acetamide), b. Butanamide (Butyramide), c. Benzamide (Benzamide)

Step-by-step solution

- Analyze Structure a

Identify the structure for part 'a' which is given as the SMILES: CC(N)=O. This is a simple amide with two carbon atoms.

- Determine IUPAC Name for Structure a

For structure a, the longest carbon chain has 2 carbon atoms. The parent alkane is ethane. Replacing the terminal –e with –amide, the IUPAC name is ethanamide.

- Determine Common Name for Structure a

For simple amides derived from common names, the corresponding carboxylic acid is acetic acid. The common name is acetamide.

- Analyze Structure b

Identify the structure for part 'b' which is given as the SMILES: CCCC(N)=O. This is a straight-chain amide with four carbon atoms.

- Determine IUPAC Name for Structure b

For structure b, the longest carbon chain has 4 carbon atoms. The parent alkane is butane. Replacing the terminal –e with –amide, the IUPAC name is butanamide.

- Determine Common Name for Structure b

For structure b, with the corresponding carboxylic acid being butyric acid, the common name is butyramide.

- Analyze Structure c

Identify the structure for part 'c' which is given as the SMILES: NC(=O)c1ccccc1. This structure features a benzene ring attached to an amide group.

- Determine IUPAC Name for Structure c

For structure c, the compound is a benzene ring with a carboxamide group attached directly to it. The IUPAC name is benzamide.

- Determine Common Name for Structure c

The common name for structure c is also benzamide, as it is widely recognized and used.

Key concepts

amides

Amides are a class of organic compounds which contain a carbonyl group (C=O) linked to a nitrogen atom (N). They are derived from carboxylic acids where the hydroxyl group (–OH) is replaced by an –NH₂ group or a substituted –NR₂ group. Amides are common in both natural and synthetic compounds and play a key role in biochemistry and industrial processes.

There are various types of amides:

• Primary amides: Contain an –NH₂ group attached to the carbonyl carbon.
• Secondary amides: Have an –NHR group attached to the carbonyl carbon.
• Tertiary amides: Feature an –NR₂ group attached to the carbonyl carbon.

Understanding their structure and naming is fundamental for students studying organic chemistry.

IUPAC nomenclature

The IUPAC (International Union of Pure and Applied Chemistry) nomenclature system is a systematic way to name chemical compounds and ensure that each has a unique name. This system prioritizes consistency and clarity, making it easier for chemists around the world to understand and communicate about specific substances.

Here is how to name amides using IUPAC rules:

• Identify the longest continuous carbon chain that includes the carbon in the carbonyl group.
• Replace the terminal –e in the corresponding parent alkane name with –amide.
• Number the carbon atoms in the chain starting from the carbonyl carbon being number 1.
• For N-substituted amides, indicate the substituents on the nitrogen using the prefix N- followed by the name of the substituent.

For example:

• Structure a: CC(N)=O is named ethanamide.
• Structure b: CCCC(N)=O becomes butanamide.
• Structure c: NC(=O)c1ccccc1 is named benzamide.

Learning these rules helps in correctly naming amides and in understanding their relationship to their parent carboxylic acids.

common names

In addition to IUPAC names, many compounds also have common names that are traditionally used in various contexts. These names are often derived from the source of the compound or its observable properties.

Common naming of amides also derives from the corresponding carboxylic acids:

• For primary amides, the suffix –ic acid in the carboxylic acid name is replaced by –amide.

Examples include:

• Acetic acid yields acetamide: CC(N)=O.
• Butyric acid yields butyramide: CCCC(N)=O.

Sometimes, the common name and IUPAC name are the same, especially for simple amides like benzamide: NC(=O)c1ccccc1. Knowing common names is helpful for recognizing and understanding references in literature and various practical settings.