Chapter 7.7, Problem 17CC

Interpretation Introduction

Interpretation:

The given mono-substituted alkene compound is more stable than given di-substituted alkene compound should be explained.

Concept Introduction:

• Alkene stability: Cis alkenes are less stable than trans alkene because of steric crowding was occurred.
• Relative stabilities of different alkenes can be determined by comparing heats given off on hydrogenation to alkanes.
• The less stable isomer is higher to being with and therefore it gives off more heat upon being hydrogenated to the alkene.
• Similar heats of hydrogen studies for various alkenes have lead to the following general statement about alkene stability.
• $tetra-substituted>tri-substituted>di-subsitiuted>mono-substituted$

Hybridization of four carbons in Cyclobutane is ${\text{sp}}^{\text{3}}$. Bond angles between ${\text{sp}}^{\text{3}}$ hybridized carbons are $109.5°$, but in cyclobutane this ${\text{sp}}^{\text{3}}$ hybridized carbon’s bond angle is constrained to $90°$.

Bond angle of ${\text{sp}}^2$ hybridized carbon is $120°$ and the bonds of  ${\text{sp}}^2$ hybridized carbons are in trigonal planar.