Question

The IUPAC name of \(\mathrm{CH}_{3}-\mathrm{CH}-\mathrm{CHO}\) is (a) Butan-2-aldehyde (b) 2-methylbutanal (c) 3-methylisobutyraldehyde (d) 3-methylbutanal

Short answer

IUPAC name is 2-methylpropanal (not listed in the options).

Step-by-step solution

Identify the Longest Carbon Chain

The compound is composed of two carbon chains. The longest continuous carbon chain involves three carbons when counted from the aldehyde group, giving us a propanal structure.

Identify Substituents

The structure shows a methyl group \((\mathrm{CH}_3)\) attached to the second carbon atom.

Assign the Root Name

The name of the longest chain with three carbons and an aldehyde group is propane, thus becomes 'propanal' when accounting for the aldehyde functional group.

Number the Carbon Chain

Number the carbon chain starting from the aldehyde carbon (as carbon 1) to give the substituent carbon the lowest number. The methyl group is on the second carbon.

Combine the Elements into the IUPAC Name

Use the substituent name and position, along with the base chain name to form the complete name: '2-methylpropanal'.

Key concepts

Chemical Structure Analysis

Chemical structure analysis is the foundational step where we closely examine the layout of atoms in a compound. Here, the task involves determining how the atoms within the compound \(\mathrm{CH}_3-\mathrm{CH}-\mathrm{CHO}\) are connected. Initially, we need to identify the types of atoms and their arrangement. This particular structure can be broken down into:

• Three carbon atoms (forming the backbone of the molecule).
• Hydrogen atoms attached to the carbon atoms.
• A terminal carbonyl group, typical of aldehydes, represented as \(\mathrm{CHO}\).

By evaluating this setup, we ascertain that the molecule is structured such that it has a longest carbon chain consisting of three carbons. Understanding the exact configuration dictates how the compound behaves chemically and how we proceed to name it correctly.

Organic Compound Naming

Organic compound naming according to IUPAC standards is essential for consistent communication among chemists. The name provides insight into the molecular composition and configuration of the given compound.To name \(\mathrm{CH}_3-\mathrm{CH}-\mathrm{CHO}\), follow these simplified steps:

• Identify the longest carbon chain including the functional group. Here, it’s a three-carbon chain with an aldehyde group, forming a propanal base.
• Identify the presence and position of any substituents. The methyl group sits on the second carbon atom, making the compound a 2-methyl derivative.
• Combine these elements following IUPAC conventions to develop the complete name: 2-methylpropanal.

These steps ensure that every aspect of the molecule’s structure is accounted for in its name, aiding in clarity and consistency.

Functional Groups Identification

Identifying functional groups is a critical aspect of understanding an organic compound's chemistry. Functional groups determine the characteristics and reactivity of the molecules they constitute.In our compound, \(\mathrm{CH}_3-\mathrm{CH}-\mathrm{CHO}\), the key functional group is the aldehyde group \(\mathrm{CHO}\). This group is:

• Characterized by a carbon double-bonded to oxygen and single-bonded to hydrogen.
• Always found at the end of the carbon chain, which significantly affects naming as the chain must include this group.

Recognition of the aldehyde group is paramount since it influences both the naming and the inherent chemical behavior of the compound. Understanding these properties is crucial for predicting reactions and interactions in organic chemistry.