Chapter 13, Problem 13.5P

Interpretation Introduction

Interpretation:

The $A_3{M}_{{}_2}{X}_4$ spectrum should be sketched, and A, M and X are protons with distinctly chemical shifts and $J_{AM}>J_{AX}>J_{MX}$ have to determined.   

Concept Introduction:

The number of signals in the ${}^1\text{H NMR}$ of any compound is equal to the number of protons that are chemically non-equivalent.  Non-equivalent protons are the protons that are present in the different chemical environment.  The equivalent protons produce the same signal which means the set of chemically equivalent protons produces only one signal.

The splitting of signals predicts the number of hydrogens or protons attached to the adjacent carbon in a carbon chain of a compound.  The single signal is split into multiple

peaks called the multiplicity of the signal.  Splitting of signals is done according to the $\left(N+\text{1}\right)$ rule.  $N$ is the number of adjacent non-equivalent protons.

According to the $\left(N+\text{1}\right)$ rule, for a proton-coupled with an $N$ adjacent non-equivalent

protons, the signal split into $\left(N+\text{1}\right)$ peak.  The splitting is mutual.  With this information,

the structure of the compound can be predicted.