• # question_answer Among the following the most reactive towards alcoholic KOH is [AIIMS 2004] A) $C{{H}_{2}}=CHBr$ B) $C{{H}_{3}}COC{{H}_{2}}C{{H}_{2}}Br$ C) $C{{H}_{3}}C{{H}_{2}}Br$ D) $C{{H}_{3}}C{{H}_{2}}C{{H}_{2}}Br$

The polarity between C-X bond increase by increasing the +I effect which increase by increasing the alkyl group by which X of C-X easily eliminate. In $C{{H}_{3}}C{{H}_{2}}C{{H}_{2}}Br$ the polarity is maximum due to 3 alkyl group while in rest polarity decrease due to the presence of double bond, presence of -CO group (-I) and less no. of alkyl group. $C{{H}_{3}}C{{H}_{2}}C{{H}_{2}}Br+KOH\xrightarrow{\text{alc}\text{.}}$$C{{H}_{3}}CH=C{{H}_{2}}+KBr+{{H}_{2}}O$