Name the following carboxylic acid derivatives, giving both a common name and an IUPAC name where possible.
(d) PhNHCOCH₂CH(CH₃)₂
(e) CH₃CONHCH₂Ph

Verified step by step guidance

1. Step 1: Analyze the structure (d) PhNHCOCH2CH(CH3)2. This compound contains a phenyl group (Ph), an amide functional group (-CONH-), and an isobutyl group attached to the carbonyl carbon. The phenyl group is directly bonded to the nitrogen atom of the amide.
2. Step 2: Assign the common name for (d). The common name for amides is derived from the carboxylic acid name, replacing 'ic acid' with 'amide.' The isobutyl group is named as a substituent. The common name for this compound is 'phenyl isobutyramide.'
3. Step 3: Assign the IUPAC name for (d). In IUPAC nomenclature, the amide is named based on the parent chain of the carboxylic acid. The phenyl group is treated as a substituent on the nitrogen atom. The IUPAC name for this compound is 'N-phenyl-2-methylpropanamide.'
4. Step 4: Analyze the structure (e) CH3CONHCH2Ph. This compound contains a methyl group (CH3), an amide functional group (-CONH-), and a benzyl group (CH2Ph) attached to the nitrogen atom of the amide.
5. Step 5: Assign the common and IUPAC names for (e). The common name is 'benzylacetamide,' derived from acetic acid. The IUPAC name is 'N-benzylacetamide,' where the benzyl group is treated as a substituent on the nitrogen atom.

Key Concepts

Carboxylic Acid Derivatives

Carboxylic acid derivatives include compounds such as esters, amides, and anhydrides, which are derived from carboxylic acids. They retain the carboxyl functional group (–COOH) but have different substituents replacing the hydroxyl group (–OH). Understanding these derivatives is crucial for naming and identifying their structures, as they exhibit distinct chemical properties and reactivity.

IUPAC Nomenclature

The International Union of Pure and Applied Chemistry (IUPAC) nomenclature provides a systematic method for naming chemical compounds. For carboxylic acid derivatives, the naming involves identifying the longest carbon chain, determining the functional groups present, and applying specific suffixes and prefixes. Familiarity with IUPAC rules is essential for accurately naming compounds and communicating chemical information.

Common Names vs. IUPAC Names

Common names are often simpler and more traditional names used for chemical compounds, while IUPAC names follow a standardized set of rules. For example, acetic acid is the common name for ethanoic acid. Understanding the difference between these naming conventions is important for recognizing compounds in both academic and practical contexts, as some compounds are more commonly referred to by their common names.