JEE Main & Advanced Chemistry GOC Question Bank Critical Thinking

  • question_answer Most stable carbonium ion is [Pb. CET 2004]

    A) \[{{\overset{+}{\mathop{C}}\,}_{2}}{{H}_{5}}\]

    B) \[{{(C{{H}_{3}})}_{3}}\overset{+}{\mathop{C}}\,\]

    C) \[{{({{C}_{6}}{{H}_{5}})}_{3}}\overset{+}{\mathop{C}}\,\]

    D) \[{{C}_{6}}{{H}_{5}}\overset{+}{\mathop{C}}\,{{H}_{2}}\]

    Correct Answer: C

    Solution :

    In the triphenyl methyl carbonium ion the p electrons of all the three benzene rings are delocalised with the vacant p-orbital of central carbon atom. So, it is resonance stabilised. It is the most stable of all the carbonium ions given The ion \[C{{H}_{3}}-\underset{C{{H}_{3}}}{\overset{C{{H}_{3}}}{\mathop{\underset{|\ \ }{\overset{|\ \ }{\mathop{{{C}^{+}}}}}\,\ \ }}}\,\] is stabilised by hyperconjugation, a second order resonance.

You need to login to perform this action.
You will be redirected in 3 sec spinner