Question

rank the following newman projections in order of decreasing energy, from least stable to most stable.

Explanation:

Step1: Understand energy - stability relationship

Higher energy means less stable. We need to analyze steric hindrance in Newman projections.

Step2: Analyze A

In A, there are multiple gauche - butane interactions between bulky isopropyl groups, leading to high steric hindrance and high energy (least stable).

Step3: Analyze B

B has some steric interactions between isopropyl groups, but less than A as the groups are not as closely arranged in a high - energy conformation.

Step4: Analyze C

C has relatively less steric hindrance compared to A and B as the bulky groups are more spread out.

Step5: Analyze D

D has the least steric hindrance among them as the bulky groups are in an anti - conformation to each other, resulting in the lowest energy (most stable).

Answer:

A > B > C > D