question_answer

Hyper conjugation (HC) and reverse hyper conjugation (RHC) both are the example of \[\sigma -\pi \] conjugation. Which one of following statement is correct about the above two electronic effect -

A) HC directing the \[{{E}^{\otimes }}\] at meta position where as RHC activates the \[{{E}^{\otimes }}\] at ortho & para position

B) HC directing the \[{{E}^{\otimes }}\] at ortho position RHC directing the \[{{E}^{\otimes }}\] at meta & para position

C) HC directing the \[{{E}^{\otimes }}\] at ortho & para position, RHC directing \[N{{u}^{\otimes }}\] at ortho & para position

D) None of these

Correct Answer: C

Solution :

Hyper conjugation is a electron donating effect increases electron density on ortho & pera position where as revers hyperconjugation is a electron with drawing, decrease electron density at ortho & pera position & oriented the coming electrophile to attack on meta position