Question #44030

Aniline undergoes electrophilic aromatic substitution with a nitrating mixture (conc. \ce{HNO3} and conc. \ce{H2SO4}) at $288\text{ K}$ to form three mononitrated products $P$, $Q$, and $R$ with yields of $51\%$, $47\%$, and $2\%$ respectively. Product $Q$ is isolated and treated with \ce{NaNO2}/\ce{HCl} at $273-278\text{ K}$, followed by reaction with \ce{H3PO2} and \ce{H2O} to yield compound $X$. In a parallel experiment, aniline is first treated with acetic anhydride in the presence of pyridine, then nitrated using the same nitrating mixture at $288\text{ K}$, and finally hydrolyzed with dilute \ce{H2SO4} to give compound $S$ as the major product. $S$ is then subjected to diazotization (\ce{NaNO2}/\ce{HCl} at $273-278\text{ K}$) followed by a Sandmeyer reaction with \ce{CuCN}/\ce{KCN} and subsequent complete acidic hydrolysis to yield compound $Y$. Identify compounds $X$ and $Y$.