Chapter G, Problem G.6P

Interpretation Introduction

Interpretation:

The mass spectrum of an amine (${\text{C}}_{\text{6}}\text{H}\text{N}$) exhibits a base peak at m/z = $\text{3}0$. Which of the following amines could give rise to that mass spectrum is to be found.

Concept introduction:

The mass of each compound is $\text{1}0\text{1}$ u.

In each case, a nonbonding electron is lost from $\text{N}$ to produce a molecular ion. The peak at m/z = 30 is due to the lost of a pentyl radical, ${\text{CH}}_{\text{3}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{2}}{}^{\text{•}}$, to form the iminium cation, ${\text{H}}_{\text{2}}{\text{C=}}^{\text{+}}{\text{NH}}_{\text{2}}$. Compound A is the only compound capable of losing a pentyl radical to form $\text{α}$-cleavage.