Chapter 18.5E, Problem 18.5P

Interpretation Introduction

Interpretation:

How the UV spectrum of the conjugated product, cholest-$4$-ene-$3$-one is different from that of cholesterol is to be described.

Concept introduction:

In ultraviolet (UV) spectra of aldehydes and ketones, the strongest absorptions are the ones that results from $\text{π}$ to ${\text{π}}^{*}$ electronic transition. In alkenes, these observations are seen at ${\text{λ}}_{\max }>200\text{nm}$ only if the carbonyl double bond is in conjugation with another double bond in the molecule.