Chapter 20, Problem 20.80P

Interpretation Introduction

Interpretation: An explanation corresponding to the fact that the $\text{β}$ carbon of an $\text{α},\text{β-}$unsaturated carbonyl compound absorbs farther downfield in the ${}^{13}\text{C}$ NMR spectrum than the $\text{α}$ carbon is to be stated.

Concept introduction: On the horizontal axis, the position of absorption is generally referred to as chemical shift. Depending upon the electron density or the concentration of electron around carbon, the chemical shift values of carbon varies relative to the reference signal. The terms, upfield and downfield expresses the relative location of signals. The meaning of upfield is to the right and of downfield is to the left.