IIT JEE Advanced 2008 Paper 2

General Explanation for Questions 39 to 41: The overall reaction sequence can be described as follows: $\underset{\text{Tertiary alcohol}}{H}$ $\xrightarrow[\Delta]{\text{Conc. }\mathrm{H}_2\mathrm{SO}_4}$ I $\xrightarrow{\text{ozonolysis}}$ J + K J $\xrightarrow{\mathrm{KOH}}$ $\mathrm{PhCH}_2\mathrm{OH}+L$ Here K is formed by aldol self-condensation, so the structure of K is $\mathrm{PhCOCH}_3$. J in presence of KOH forms benzyl alcohol and L by Cannizzaro’s reaction, so structure of L is $\mathrm{PhCOO}^{-}$. Since J and K are obtained by ozonolysis of I, so the structure of I is Ph-CH = $\mathrm{C}(\mathrm{CH}_3)\mathrm{Ph}$. The structure of tertiary alcohol H is $\mathrm{Ph}-\overset{\mathrm{O}}{\overset{\parallel}{\mathrm{C}}}-\mathrm{CH}_3+\mathrm{PhCH}_2\mathrm{MgBr}$ → $\mathrm{Ph}-\overset{\mathrm{OH}}{\overset{\vert}{\underset{\mathrm{H}_2\mathrm{C-Ph}}{\underset{\vert}{\mathrm{C}}}}}-\mathrm{CH}_3$ - H