UrbanPro
true

Take Class 12 Tuition from the Best Tutors

  • Affordable fees
  • 1-1 or Group class
  • Flexible Timings
  • Verified Tutors

Electrophilic Aromatic Substitution (EAS)

Akshay
17/02/2017 0 0

Electrophilic Aromatic Substitution

 

Note why we’re calling it substitution: we’re breaking C-H and we’re forming a different bond at C (e.g. Cl, Br, N, S, C, etc.)

Here’s some key points:

  • The aromatic ring is the nucleophile here. So if we make the electron ring more electron rich, we’ll increase the rate of reaction [groups like OH, OCH3, NH2, or alkyl groups are good examples]
  • The electrophile (e.g. Cl2, Br2, etc.) is usually not reactive enough by itself to react with the aromatic ring. That’s where the catalyst comes in. [There isn’t any significant difference between aluminum (Al) and iron (Fe) catalysts – it’s textbook dependent.
  • The catalyst (always an acid or Lewis acid) accepts a pair of electrons from the electrophile. Since we’re taking electrons away from the electrophile, it becomes more electrophilic! Then it becomes reactive enough for the aromatic group to add to it. 
  • A short-lived carbocation intermediate is formed. 
  • Finally, a weak base comes along and re-forms the double bond, restoring aromaticity. This step is a lot like the last step of the E1 elimination mechanism. 
0 Dislike
Follow 0

Please Enter a comment

Submit

Other Lessons for You

Isotopes-1
1) What is an Isotope? Isotopes are atoms of the same element that have different numbers of neutrons but the same number of protons and electrons. 2) What determines the atomic number of an element? A...

Like to solve the following problem?
Consider the following : A particle moves along a straight line as per law:Power is proportional to displacement raised to power -3/2. That is,P∝S-3/2.Then, acceleration is proportional to which...

Derive An Expression For Drift Velocity Of Free Electrons
Derive an expression for drift velocity of free electrons. How does drift velocity of electrons in a metallic conductor vary with increase in temperature ? Explain. (i) When conductor is subjected to...


Most important aspect in answering in JEE/NEET exams: Time Management w. r. t. Choosing of Questions
Generally, the students do not plan out how much time to spend on various questions. In most cases, they try to attend questions in the order of the paper. They spend more time on the earlier questions...
D

Dr. Mrinmoy Garai

0 0
0
X

Looking for Class 12 Tuition Classes?

The best tutors for Class 12 Tuition Classes are on UrbanPro

  • Select the best Tutor
  • Book & Attend a Free Demo
  • Pay and start Learning

Take Class 12 Tuition with the Best Tutors

The best Tutors for Class 12 Tuition Classes are on UrbanPro

This website uses cookies

We use cookies to improve user experience. Choose what cookies you allow us to use. You can read more about our Cookie Policy in our Privacy Policy

Accept All
Decline All

UrbanPro.com is India's largest network of most trusted tutors and institutes. Over 55 lakh students rely on UrbanPro.com, to fulfill their learning requirements across 1,000+ categories. Using UrbanPro.com, parents, and students can compare multiple Tutors and Institutes and choose the one that best suits their requirements. More than 7.5 lakh verified Tutors and Institutes are helping millions of students every day and growing their tutoring business on UrbanPro.com. Whether you are looking for a tutor to learn mathematics, a German language trainer to brush up your German language skills or an institute to upgrade your IT skills, we have got the best selection of Tutors and Training Institutes for you. Read more