3/12/2018 05:00 PM O 9.4/103/10/2018 03:37 PM Gradebook Print CalculatorPeriodic

Question

3/12/2018 05:00 PM O 9.4/103/10/2018 03:37 PM Gradebook Print CalculatorPeriodic Table Question 5 of 10 IncorrectIncorrect Incorrect Map A Sapling Learning macmillan learning Substituents on an aromatic ring can have several effects on electrophilic aromatic substitution reactions Substituents can activate or deactivate the ring to substitution, donate or withdraw electrons inductively, donate or withdraw electrons through resonance, and direct substitution either to the ortho/para or to the meta positions. From the following lists, select the substituents that have the indicated property. The substituents are written as -XY, where X is the atom directly bound to the aromatic ring Activation of the ring towards substitution Withdrawal of electrons through resonance Ortho/para-directed substitution CH3 CN OH -NO2 NH2 OCOCH -CN -COOH CF3 OCH3 OH SO3H Substituents that withdraw electrons through resonance have a bond that can conjugate with the system of the ring Previous Give Up & View Solution # Try Again Next- Exit

Explanation / Answer

In Electrophilic aromatic substitution reaction ,Activating substituents stabilize the cationic intermediate formed during substitution by donating electrons into the ring system, through inductive effect or resonance effect ie

And, the substituent which favours Electrophilic aromatic substitution by increasing electron density on the ring are :

- groups having +I effect

- groups having +R effect

These are generally orhro, para directing. And these are the activating groups.

And substituent which don't favour Electrophilic aromatic substitution reaction are:

- groups having electron withdrawing effect ie -R and - I

these are generally meta directing groups. And, these are the destabilized group towards electrolhilic substitution reaction.

So,

* ACTIVATION OF RING TOWARDS SUBSTITUTION :by groups CH3 and OH due to +I and +R effect ie electron releasing nature.

-CN and NO2 have -R effect ie electron withdrawing effect so, they are deactivating groups.

* WITHDRAWAL OF ELECTRONS THROUGH RESONANCE : by groups which are having -R effect, ie COOH and - CN

* ORTHO/PARA DIRECTED SUBSTITUTION : by groups which are having , - I, +I, and +R effect, ie - F (which is having - I effect), - OCH3 and - OH (which are having +R effect).

Related Questions

Navigate

• Browse (All)
• Browse 3
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.