Chapter 14, Problem 14.25P

Identify products A and B from the given ${}^{\text{1}}\text{H}$ NMR data.

a. Treatment of ${\text{CH}}_{\text{2}}={\text{CHCOCH}}_{\text{3}}$ with one equivalent of $\text{HCl}$ forms compound A. A exhibits the following absorptions in its ${}^{\text{1}}\text{H}$ NMR spectrum: $2.2\left(\text{singlet, 3H}\right)\text{, 3}\text{.05}\left(\text{triplet, 2H}\right)$ and $\text{3}\text{.6}\left(\text{triplet, 2H}\right)\text{ppm}$. What is the structure of A.

b. Treatment of acetone $\left[{\left({\text{CH}}_{\text{3}}\right)}_{\text{2}}\text{C}=\text{O}\right]$ with dilute aqueous base forms B. Compound B exhibits four singlets in its ${}^{\text{1}}\text{H}$ NMR spectrum at $\text{1}\text{.3}\left(\text{6 H}\right)\text{, 2}\text{.2}\left(\text{3 H}\right)\text{, 2}\text{.5}\left(\text{2 H}\right)$ and $\text{3}\text{.8}\left(\text{1 H}\right)\text{ppm}$. What is the structure of B?