Question

4) A) Explain the regiochemistry of the following bromination using key resonance structures (there should be three) and predict the final product. Hint: Drawing these resonance structures is key to tell you if this substituent will direct bromination ortho/para or meta (3 polnts for the correct product, 4 polnts for the resonance structures, 7 points total). Brz FeBr, B) Predict the products (3 points each). b) OCH, a) HNO, H,SO AIC Br 1) S c) (p P. CH PHPh "Chem 432 lab" NO, Ph CI 2) Zn/HCI SO H,SO. MeCl AICI, C) Rank the following arenes in order of DECREASING reactivity for SEAr (i.e. fastest to slowest, 10 points all or nothing). Осн, OCH, NO CH OCH

Answer 1

1.
Telira & all is the electron withdrawing group which direct the substitcent to meta position. Mechanism Big & Te Bra Brf By - Febre Е гер, & Brt Br (mason) • Because dectron withdrawing group will withdraw the electron density less electron density will be creceled at ortho and para • So the ortho- para will not be stable for substitution because of less clectron deasily • Meta position is the stable and having electron density better than ortho, post para So the substituent will go at meta position oor oor oor 1 4 11 EC) resonance structure • In the resonance struchure shown above the charge are cet ortho , parce position " which makes less election density • At meta position the charge is not present so that substituent will predey meda position for attack

AlCl3 (60%) (406) Coobocation fromed in this friedel-Couft alkylelion let the will undergo molecular rearrangement and is o product will get And the substituent present at benzene will direct the substituent at ortho and para position • beet due to bulky group present at benzene ring the attack of ortho position will hindered by bulky group so, para product will formed CH₂ - CH2 - CH2 - AlCl3 CH3-CH2-ci +AICI CH₂-CH-CH₂, Alchu a 'CH3-CH2 - CH2 Alche GÐ [Chorchilla ) 180.) (40 lmajor product I