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Which are the possible products from this reaction?enter image description here

The answer in the mark scheme shows that it should be as demonstrated as pic A. However, I think it could be either A. or B. since both substituted groups of the benzene ring, NH2 and Cl, direct the incoming electrophiles to attack the 2,4 and or 6 positions. Do I understand correctly?

I have never come across two substituted groups before. Should I consider both NH2 and Cl as substituted groups or only one of them, but which one? Also, how to count the position of carbon on the benzene ring in this case? enter image description here

Please help! Any help would be much appreciated.:)

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    $\begingroup$ Aniline directs o/p, chlorobenzene is weaker but directs m. The effects are additive $\endgroup$ – Waylander Mar 9 '17 at 10:44
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    $\begingroup$ I thought halogens dieected o/p (except $\cw{F}$, maybe), bbut more weakly than an amino group. $\endgroup$ – Oscar Lanzi Mar 9 '17 at 11:26
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On substituting an already substituted benzene ring, you need to know which kind of substitution takes place; It is electrophillic substitution that is taking place.

Then can you now think about the correct choice? $\ce{-NH2}$ has a greater positive mesomeric effect (+M effect) in comparison to the Halogen groups.

Since the para position with respect to $\ce{-NH2}$ is already occupied by chlorine the ortho position would be attacked.

What we come to know is that since $\ce{-NH2}$ creates more electron availability in comparison to halogen it leads to "electrophilic substitution" on ortho position with respect to $\ce{-NH2}$.

And moreover $\ce{-NH2}$ group since a very very strong electron donor so once again another substitution of next bromine takes place at the other ortho position with respect to $\ce{-NH2}$.

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  • $\begingroup$ I have updated your post with chemistry markup. If you want to know more, please have a look here and here. We prefer to not use MathJax in the title field, see here for details. $\endgroup$ – Martin - マーチン Mar 9 '17 at 12:31

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