ChemistryJEE Main 21 Jan 2026, Shift 1·Q4·MCQ·Moderate

Hydrocarbons · Electrophilic addition to alkenes

A hydrocarbon ‘P' (

\ce{C4H8}

) on reaction with HCl gives an optically active compound ‘Q' (

\ce{C4H9Cl}

) which on reaction with one mole of ammonia gives compound ‘R' (

\ce{C4H11N}

). ‘R' on diazotization followed by hydrolysis gives ‘S'. Identify P, Q, R and S.

We corrected a printing error in the original paper

Option (3): source printed R as “CH $_3$ –CH $_2$ =CH(NH $_2$ )–CH $_3$ ” (a pentavalent carbon); the “=” in the figure is corrected to the intended single bond “CH $_3$ –CH $_2$ –CH(NH $_2$ )–CH $_3$ ” (butan-2-amine).

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