Ramendra C Mukerjee Solutions for Chapter: Empirical, Molecular and Structural Formulae, Exercise 1: PROBLEMS

An alkene $\left(\mathrm{A}\right)$, on ozonolysis yields acetone and an aldehyde. The aldehyde is easily oxidised to an acid $\left(\mathrm{B}\right)$. When $\left(\mathrm{B}\right)$ is treated with bromine in presence of phosphorus, it yields compound $\left(\mathrm{C}\right)$ which on hydrolysis gives a hydroxy acid $\left(\mathrm{D}\right)$. The acid can also be obtained from acetone by the reaction with hydrogen cyanide followed by hydrolysis. Identify the compounds $\left(\mathrm{A}\right),\left(\mathrm{B}\right),\left(\mathrm{C}\right)$ and $\left(\mathrm{D}\right)$.

An organic compound $\left(\mathrm{A}\right)$ having molecular weight, $58,$ contained $62.06\%$ of $\mathrm{C}$ and $10.35\%$ of $\mathrm{H}$ and rest, oxygen. $\left(\mathrm{A}\right)$, on reduction gave $\left(\mathrm{B}\right)$ which gave iodoform test. $\left(\mathrm{B}\right)$, on dehydration, gave an unsaturated hydrocarbon $\left(\mathrm{C}\right)$ having molecular weight $42$. Find $\left(\mathrm{A}\right), \left(\mathrm{B}\right)$ and $\left(\mathrm{C}\right)$

An aromatic compound $\left(\mathrm{X}\right)$ contains $\mathrm{C} (79.25\%)$ and $\mathrm{H} (5.66\%)$. $\left(\mathrm{X}\right)$ on treatment with alkali, gave a neutral product $\left(\mathrm{Y}\right)$ containing $\mathrm{C} (77.78\%)$ and $\mathrm{H} (7.41\%)$ and the sodium salt of an aromatic organic acid $\left(\mathrm{Z}\right)$ which on distillation with soda lime gave benzene. Assign structural formulae to $\left(\mathrm{X}\right),\left(\mathrm{Y}\right)$ and $\left(\mathrm{Z}\right)$.

An aromatic compound $\left(\mathrm{X}\right)$ contains $58.5\%$ of $\mathrm{C}$, $4.1\%$ of $\mathrm{H}$ and $11.4\%$ of $\mathrm{N}$. $\left(\mathrm{X}\right)$ may be obtained by the action of ${\mathrm{HNO}}_3$ on a compound $\left(\mathrm{Y}\right)$. $\left(\mathrm{X}\right)$ on reduction gives a monoacidic organic base $\left(\mathrm{Z}\right)$. Give structural formulae of $\left(\mathrm{X}\right),\left(\mathrm{Y}\right)$ and $\left(\mathrm{Z}\right)$.

An aliphatic amine $\left(\mathrm{X}\right)$ contains $\mathrm{C} (61.01\%)$, $\mathrm{H} (15.25\%)$ and $\mathrm{N} (23.74\%)$. $\left(\mathrm{X}\right)$ on treatment with ${\mathrm{HNO}}_2$ gave an alcohol $\left(\mathrm{Y}\right)$ having $\mathrm{C} (60\%)$ and $\mathrm{H} (13.33\%)$. $\left(\mathrm{Y}\right)$ on careful oxidation gave $\left(\mathrm{Z}\right)$ of vapour density $29$. $\left(\mathrm{Z}\right)$ gave iodoform test. Assign structural formulae to $\left(\mathrm{X}\right),\left(\mathrm{Y}\right)$ and $\left(\mathrm{Z}\right)$.

An organic compound $\left(\mathrm{A}\right)$ contains $\mathrm{C}=32\%, \mathrm{H}=6.66\%$ and $\mathrm{N}=18.67\%$. On reduction, it gives a primary amine $\left(\mathrm{B}\right)$ which gives ethyl alcohol with nitrous acid. $\left(\mathrm{B}\right)$ gives an offensive odour on warming with ${\mathrm{CHCl}}_3$ and $\mathrm{KOH}$ and forms compound $\left(\mathrm{C}\right)$ which on reduction forms ethyl methyl amine. Assign the structures of $\left(\mathrm{A}\right),\left(\mathrm{B}\right)$ and $\left(\mathrm{C}\right)$ and explain.

Compound $\left(\mathrm{A}\right)$ gives positive Lucas test in $5$ $\mathrm{minutes}$. When $6 \mathrm{g}$ of $\left(\mathrm{A}\right)$ is treated with $\mathrm{Na}$ metal, $1120 \mathrm{mL}$ of ${\mathrm{H}}_2$ is evolved at $\mathrm{STP}$. Assuming $\left(\mathrm{A}\right)$ to contain one atom of oxygen per molecule, write the structural formula of $\left(\mathrm{A}\right)$.

An organic compound $\left(\mathrm{A}\right)$ of molecular weight $140.5$ has $68.32\%$ $\mathrm{C}$, $6.4\%$ $\mathrm{H}$ and $25.26\%$ $\mathrm{Cl}$. Hydrolysis of $\left(\mathrm{A}\right)$ with dilute acid gives compound $\left(\mathrm{B}\right)$, ${\mathrm{C}}_8{\mathrm{H}}_{10}\mathrm{O}$. Compound $\left(\mathrm{B}\right)$ can be oxidised under mild condition to compound $\left(\mathrm{C}\right)$, ${\mathrm{C}}_8{\mathrm{H}}_8\mathrm{O}$. Compound $\left(\mathrm{C}\right)$ forms a phenyl hydrazine $\left(\mathrm{D}\right)$ with ${\mathrm{C}}_6{\mathrm{H}}_5{\mathrm{NHNH}}_2$ and gives a positive iodoform test. Give the structures of compounds $\left(\mathrm{A}\right)$ to $\left(\mathrm{D}\right)$.