Question

c) Draw resonance structures of all the arenium cation intermediates and use them to explain the stability trend (obtained using B3LYP/6-31G(d)) of the three optimized regioisomeric arenium cation intermediates. (7 pts)

these are the 3 arenium cations:

Answer 1

Nitration browo be и709 : H₂SO4 + HO-NO2 * H2O + NO + Hisoa Ortho-position ier: bromonium&ion NO2 meta position NUN NO2 para position » No, Br: cior, : BP: NOL NO Un

It shows that when attacks af on the and para -position, there are four resonance structures, But when attacks at me ta position, there are three resonance structures. So, Higher soo resonance structures gives highen stability of this structures, So, para, and or the position (Nitration) is more favorable than me ta position. But para position is more favorable than ortho - position. due to there are some sferic hinder .. So, stability order of arenium cations → BP ob es