Draw the most stable conformation of
b. trans-1-tert-butyl-2-methylcyclohexane.

Verified step by step guidance

1. Identify the cyclohexane ring and the substituents: In this problem, we have a cyclohexane ring with a tert-butyl group and a methyl group attached at the 1 and 2 positions, respectively.
2. Understand the 'trans' configuration: The 'trans' configuration means that the two substituents are on opposite sides of the cyclohexane ring. One will be axial and the other equatorial.
3. Draw the chair conformation of cyclohexane: Cyclohexane can adopt a chair conformation, which is the most stable due to minimized steric strain. Draw the chair structure with alternating axial and equatorial positions.
4. Place the tert-butyl group: The tert-butyl group is bulky, so it should be placed in the equatorial position to minimize steric hindrance. Choose one carbon (C1) and place the tert-butyl group equatorially.
5. Place the methyl group: Since the configuration is 'trans', the methyl group should be placed on the opposite side of the ring from the tert-butyl group. If the tert-butyl is equatorial, the methyl group should be axial on the adjacent carbon (C2).

Key Concepts

Cyclohexane Conformations

Cyclohexane can adopt several conformations, with the chair conformation being the most stable due to minimized steric strain and torsional strain. Understanding the chair conformation is crucial for determining the stability of substituted cyclohexanes, as it allows for the analysis of axial and equatorial positions of substituents.

Axial and Equatorial Positions

In the chair conformation of cyclohexane, substituents can occupy axial or equatorial positions. Axial positions are parallel to the axis of the ring, while equatorial positions extend outward. Equatorial positions are generally more stable for bulky groups due to reduced steric hindrance, which is essential for determining the most stable conformation of substituted cyclohexanes.

Trans Configuration

The trans configuration in cyclohexane refers to substituents being on opposite sides of the ring. For trans-1-tert-butyl-2-methylcyclohexane, this means the tert-butyl and methyl groups are positioned across from each other. Understanding this configuration helps in correctly placing substituents in the chair conformation to achieve the most stable arrangement.