Question

(c) The scheme below shows a synthetic route to produce Benzocaine, a topical pain relief drug. Step 1 Step 2 O2N G H H2N KMnO4 Step 3 H2N Benzocaine COOEt Step 4 H2N J COOH (i) Provide the reagents and reaction conditions you would use in Step 1 to prepare compound H from compound G. (1 mark) (ii) Step 1 is an example of an electrophilic aromatic substitution (EAS). Draw out the EAS reaction mechanism for step 1 in the above process. In your answer you should include the equilibrium which generates the attacking electrophilic species. (6 marks) (iii) What type of reaction is taking place in Step 2? (1 mark) (iv) Provide the reagents and reaction conditions you would use in Step 2, to prepare compound I from compound H. (1 mark) (v) Provide the reagents and reaction conditions you would use in Step 4, to prepare Benzocaine from compound J. (1 mark) (vi) When you perform step 1 in the lab you notice that there are two major isomers formed. You separate the unwanted isomer before proceeding. Draw the structure of the unwanted isomer. (1 mark) (vii) Provide an explanation why this isomer was formed from the reagents and conditions used in step 1. (1 mark)

          (c) The scheme below shows a synthetic route to produce Benzocaine, a topical pain
relief drug.
Step 1
Step 2
O2N
G
H
H2N
KMnO4 Step 3
H2N
Benzocaine
COOEt
Step 4
H2N
J
COOH
(i) Provide the reagents and reaction conditions you would use in Step 1 to prepare
compound H from compound G.
(1 mark)
(ii) Step 1 is an example of an electrophilic aromatic substitution (EAS). Draw out
the EAS reaction mechanism for step 1 in the above process. In your answer
you should include the equilibrium which generates the attacking electrophilic
species.
(6 marks)
(iii) What type of reaction is taking place in Step 2?
(1 mark)
(iv) Provide the reagents and reaction conditions you would use in Step 2, to
prepare compound I from compound H.
(1 mark)
(v) Provide the reagents and reaction conditions you would use in Step 4, to
prepare Benzocaine from compound J.
(1 mark)
(vi) When you perform step 1 in the lab you notice that there are two major isomers
formed. You separate the unwanted isomer before proceeding. Draw the
structure of the unwanted isomer.
(1 mark)
(vii) Provide an explanation why this isomer was formed from the reagents and
conditions used in step 1.
(1 mark)

Show more…

c the scheme below shows a synthetic route to produce benzocaine a topical pain relief drug step 1 step 2 o2n g h h2n kmno4 step 3 h2n benzocaine cooet step 4 h2n j cooh i provide the reagen 30334

Added by Zachary L.

Chemistry: Structure and Properties

Nivaldo Tro 2nd Edition

Instant Answer

Solved by Expert Rajesh Singh

01/09/2022

Step 1

Step 1: (i) Reagents and conditions for Step 1: $$HNO_3, H_2SO_4$$ Show more…

Show all steps

lock

Thanks for your feedback!

(c) The scheme below shows a synthetic route to produce Benzocaine, a topical pain relief drug. Step 1 Step 2 O2N G H H2N KMnO4 Step 3 H2N Benzocaine COOEt Step 4 H2N J COOH (i) Provide the reagents and reaction conditions you would use in Step 1 to prepare compound H from compound G. (1 mark) (ii) Step 1 is an example of an electrophilic aromatic substitution (EAS). Draw out the EAS reaction mechanism for step 1 in the above process. In your answer you should include the equilibrium which generates the attacking electrophilic species. (6 marks) (iii) What type of reaction is taking place in Step 2? (1 mark) (iv) Provide the reagents and reaction conditions you would use in Step 2, to prepare compound I from compound H. (1 mark) (v) Provide the reagents and reaction conditions you would use in Step 4, to prepare Benzocaine from compound J. (1 mark) (vi) When you perform step 1 in the lab you notice that there are two major isomers formed. You separate the unwanted isomer before proceeding. Draw the structure of the unwanted isomer. (1 mark) (vii) Provide an explanation why this isomer was formed from the reagents and conditions used in step 1. (1 mark)

Play audio

Feedback

Powered by NumerAI

Rajesh Singh and 82 other subject Chemistry 101 educators are ready to help you.

Ask a new question

Labs

Want to see this concept in action?

NEW

Explore this concept interactively to see how it behaves as you change inputs.

View Labs

Key Concepts

Recommended Videos

Recommended Textbooks

Transcript

0:00 Hello everyone.

00:01 Let us see the following question.

00:03 Benzocaine 5 is a local anesthetic which is formed from 4 amino benzoic acid.

00:10 So this is the preparation of benzoic.

00:18 Benzocane, which is given in structure 5.

00:21 So let us see the preparation given in the question.

00:24 So here we have a preparation of benzokane.

00:27 So benzokane is given in structure 5 here.

00:31 So let us answer the questions 1 by 1 .5.

00:33 So, the question a about this sequence is, so it is all about the structure 5, suggest three steps in the synthesis of structure 4.

00:44 Now the structure 4 is 4 amino benzoic acid, we have to use a starting material as a tolwin and you have to comment on the regiose selectivity of any electrophilic substitution reaction.

00:57 So we have to use a starting material as a toll win.

01:01 So, we have tolvin, that is carbon having three hydrogen.

01:06 From there, we have to produce a structure of 4 that is 4 amino benzoic acid.

01:11 So, for tall win, first of all, it has to be converted to benzoic acid.

01:17 We have to use oxidizing agents like a kmno4.

01:21 So, on oxidation, the toll win group, that is the side chain, oxidizes to carboxylic acid.

01:28 So, the three hydrogen is converted to three oh groups on the carbon.

01:33 So, the three oh groups out of which one water is eliminated to form carboxylic group, c double bond oh.

01:40 This is the carboxylic group.

01:42 Now, we know that carboxylic group is an electron withdrawing group.

01:46 As it withdraws the electron from the ring, it mostly stays at, it is a, it is actually meta directing group.

01:56 So, that is, if it is a meta directing group, further, when electrophile is substituted, the electrophile has to substitute in the meta place.

02:08 However, it is been given as position 4.

02:10 So, this is not the appropriate method.

02:13 So, let us use a tolwin and use some other method.

02:17 So, this is not the appropriate method that we can use.

02:20 So, we can rule out this method.

02:22 So, let us try the same tollwing.

02:24 But instead of doing oxidation first, let us start doing the nitration first...

Ace is your personal tutor. It breaks down any question with clear steps so you can learn.

Start Using Ace

Continue solving this problem

Create a free account to:

View full step-by-step solution
Ask follow-up questions with Ace AI
Save progress and study later