Organic Chemistry Question

[DrHJ]

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This is related to Q29 from Destroyer:
The thing that I don't get is the difference between these two sequences of reagents for reaction with benzene to synthesize

a) Cl2, FeCl3; HNO3, H2SO4; H2, Pt
d) HNO3, H2SO4; Cl2, FeCl3; H2, Pt

 

[jz123]

Let s look at a first. In a, Cl is first added to the aromatic ring, and Cl is ortho/para director even though it is deactivating. So if you add NO2 later, it would go to either ortho or para position.

In d, you add a strong e- withdrawing NO2 group 1st, and NO2 is meta director, after that, if you add Cl, it would go to the meta position only. So d is the correct answer.

 

[dentalstudent2021]

D is the answer ?
it all comes down to donating/withdrawing groups and ortho/para/meta groups. for our answer to be the molecule above you need to follow choice D. first add HNO3, which adds NO2 to the benzene. NO2 is an electron withdrawing group and directs META. Then you add Cl2 which adds Cl to the meta position! now you want NH2 which you get by reducing NO2 via H2,Pt

 

[super frank]

Know your o/p-directors vs. m-directors.

 

[DrHJ]

Thanks,
I totally forgot and Cl is ortho/para director despite of being a withdrawing group. Thanks everybody. The answer is D