Question

from the organic compounds: follow-up activity, exercise 3-1 asked the question: which ring sizes are neither significantly strained, i.e., rings which were difficult to close, nor puckered, i.e., rings in which the carbon atoms cannot be placed in a plane without ring strain? select all possible answers from the list below that best answers this question based on the assigned lab activities. question 3 options: cyclopropane cyclobutane cyclopentane cyclohexane cycloheptane none of the above

Answer 1

Cyclopentane and cyclohexane are rings which are neither significantly strained nor puckered, making them stable and common in nature. Cyclopentane has minimal ring strain and cyclohexane has a strain-free chair conformation.

Step-by-step explanation:

Ring sizes that are neither significantly strained nor puckered are cyclopentane and cyclohexane. Cyclopropane and cyclobutane suffer from substantial ring strain due to their small size and sharp deviation from the ideal sp³ hybridized bond angle of 109.5°. Cyclopentane has a minimal ring strain and adopts a puckered envelope conformation, which makes it one of the most common ring structures in nature, like in ribose and fructose. Cyclohexane, on the other hand, attains a strain-free chair conformation to accommodate the near-ideal bond angles close to the tetrahedral value. Larger rings such as cycloheptane may experience some transannular strain but are less strained compared to smaller rings. Cyclohexane is the most common ring structure found in nature, due to its zero ring strain. Hence, from the given options, cyclopentane and cyclohexane are rings which are neither significantly strained nor puckered.