Chapter 14, Problem 14.76P

Because ${}^{\text{31}}\text{P}$ has an odd mass number, ${}^{\text{31}}\text{P}$ nuclei absorb in the NMR and, in many ways, these nuclei behave similarly to protons in NMR spectroscopy. With this in mind, explain why the ${}^{\text{1}}\text{H}$ NMR spectrum of methyl dimethylphosphonate, ${\text{CH}}_{\text{3}}\text{PO}{\left({\text{OCH}}_{\text{3}}\right)}_{\text{2}}$, consists of two doublets at $1.5$ and $\text{3}\text{.7}\text{ppm}$.