9:11 1CH237 Pre-recita...d) Look closely at the EDG groups, what do you notice about the atom which attacheddirectly to the ring? Are there similarities between these atoms? (R stands for anycarbon attachment, not all lone pairs have been drawn in)e) Now look at the EWG groups, what do you notice about the atom which attacheddirectly to the ring? Look at the bonds to these atoms? Look at partial charges(bonddipole) or formal charges on these atoms. Again, are there similarities?NOTE: All EWGS shown are meta directing and are deactivating. All EDGS shownare ortho/para directing and activating.II. Substitution on Di-substituted benzene ringsWhen a ring has two groups on it, then the following rules are applied:i) When two activating groups are attached to the ring, the stronger activator directsplacement of the electrophile.i) When an activator and deactivator are attached to the ring, the activator directs placementof the electrophile.i) Placement of an electrophile between two groups is often unfavorable due to steric effects.a) In each of the following, predict the directing effects. Indicate position(s) on the ringwith (an) arrow(s) where an electrophile might be directed.StrongActiyatorWeakActivatorStrongActivatora)b)c)StrongDeactivatorStrongd.DeactivalorWeakWeakActivatorActivatorweakStrongActivatorStrongDeactivatorWeakActivatord)e)b) Indicate with an arrow the favored position(s) of substitution in the nitration of thefollowing compounds, and explain your choice(s):а) но—COOHсоонb) H,C--C(CH,hOHc) O,N-CHCHCHIV. Challenge ProblemThe mechanism of a Friedel-Crafts alkylation is explained by a video in the ebook inChapter 22. Watch this video then provide a valid mechanism which explains theproducts formed in the reaction shown. All electron movement must be indicated witharrows and all intermediates must be shown in order to receive full credit. Eachgroup will do two mechanisms.ACI.6DashboardCalendarTo DoNotificationsInbox因 Electrophilic Aromatic SubstitutionI.Lewis Acid catalystElectrophilic addition of Cl2 or Br2 to an aromatic ring requires the presence of aLewis acid catalyst such as FeCla, FeBr3, AICI3, or AIBR3.a) Why are these compounds considered Lewis acids?b) Why is a Lewis acid catalyst necessary for Cl2 or Br2 to react with an aromaticring?c) Draw the side product which will be formed if you attempt to synthesizechlorobenzene using FeBr3 and Cl2.II. MechanismConsider the mechanism shown below for chlorination of a monosubstituted aromatic ring.CICI-Fe-CÇI FeCl,Fe-CICIFeClaCIÇI FeCla+ HCI + FeCl3a) In this reaction is the aromatic ring behaving as an electrophile or a nucleophile?b) Why is FeCla considered a catalyst in the reaction shown?c) Which would you expect to be faster, an electrophilc aromatic substitution inwhich the Z group is an electron donating group or an electron withdrawing group?Explain your answer.Below is a chart showing common electron donating and withdrawing groups.Electron-Withdrawing Groups (EWG)రంరంరంOHCNO=S=0НОROvery strong EWGElectron-Donating Groups (EDG)RR NHROROHNH2NR2weak EDGvery strong EDG

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