ISSUE:

Hello good morning, I did not know how to put the title of this. I have an exercise that asks me to find the path of 2 compounds but with the condition of using sulfonation as a protecting group to direct subsequent incoming groups.

I have made a few attempts, but I don't know if they are 100% correct or if the correct route would be another, or if there is a more appropriate one.

In this first case, from acetophenone to reach 2-bromobenzoic acid

Broadly my logic has been: 

• deactivating acetyl group, I have to activate it so I reduce it to alcohol (activating group, although in this case it's not directly attached, so I don't know how that would affect that)
• then sulphate and direct to stop
• After ortho halogen, only viable sites
• Oxide to recover the carbonyl group
• Desulfon

In case 2, I am asked to arrive at o-methylaniline from benzene itself.



The logic for this has been roughly:

• A nitration and subsequent reduction with H2 on Nickel to obtain the activating group
• Sulfonation
• Fridel crafts with 1 mol of methyl chloride as a reagent in lewis acid
• desulfonation

This is what I have been able to do with the range of reactions that I am aware of up to now, I am looking and studying the book, even if there is some reaction or some step that can be changed.

But broadly speaking, what worries me the most is that he has taken some step that cannot be taken or is not the most appropriate since, after all, paper can withstand everything.

Is it good in general terms or should I consider some detail?

All the best! Many and a million thanks as always

Ok, ok, ok, I just realized when I launched the post, that the first case, I didn't get the 2-bromo benzoic acid.

• Instead of reducing to alcohol, I must reduce to the alkyl chain by means of Clemmensen reduction, for example.
• then I continue with the normal steps and at the end I do an oxidation of the alkyl chain with potassium permanganate in an alkaline medium and heat,
  
  removing this blunder where I have obtained another molecule, would the intermediate reactions be okay?

The first case is perfect:
1. WK or Clemmensen
2. Sulfonate
3. Bromar
4. Deprotection for
5. Chain oxidation.

In the second case, the sequence is correct, but it requires the protection of the amino group before sulfonation, since in acidic media it is protonated and becomes meta oriented.

Greetings!!!

Thank you so much!! What a joy it gives me to know that I am on the right track. Greetings!