question_answer 1)

  Which of the following are correct? (a)\[C{{H}_{3}}-O-CH_{2}^{\oplus }\] is more stable than \[C{{H}_{3}}-CH_{2}^{\oplus }\] (b) \[{{(C{{H}_{3}})}_{2}}C{{H}^{\oplus }}\]is less stable than \[C{{H}_{3}}-C{{H}_{2}}-CH_{2}^{\oplus }\] (c)  \[C{{H}_{2}}=CH-CH_{2}^{\oplus }\]is more stable than \[C{{H}_{3}}C{{H}_{2}}CH_{2}^{\oplus }\] (d) \[C{{H}_{2}}=C{{H}^{\oplus }}\]is more stable than \[C{{H}_{3}}-CH_{2}^{\oplus }\]

Answer:

  (a, c) is stabilized by strong resonance effect while \[C{{H}_{3}}\to -\overset{+}{\mathop{C}}\,{{H}_{2}}\]is stabilized by only weak \[+I\] effect of \[C{{H}_{3}}\] group. is stabilized by strong resonance effect while \[C{{H}_{3}}C{{H}_{2}}\to -\overset{+}{\mathop{C}}\,{{H}_{2}}\] is stabilized by weak \[+I\] effect of the \[C{{H}_{2}}C{{H}_{3}}\] group.