Chapter 7, Problem 40P

Suggest an explanation for the fact that $\text{1-methylcyclopropene}$ is some $\text{42 kJ/mol}$

( $\text{10 kcal/mol}$) less stable than methylenecyclopropane.

 

On the basis of your answer to part (a), compare the expected stability

of $3$-methylcyclopropene with that of $1$-methylcyclopropene and that of methylenecyclopropane.