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For this I have to convert benzene into the product in the box using the reagents listed. The order of reagents that makes sense to me is IDGBEH. However, this is not the correct answer. Somewhere I am missing 2 steps to the synthesis and I am at a complete loss. I understand all of the basic and complex concepts of organic chemistry we've covered in my class thus far, so I'm confused as to how my proposed mechanism has an issue. If it's any help I know the mechanism is supposed to be 8 steps.

In my mind IDGBEH makes complete sense and should give me the product that I want, unless I am missing something or I misunderstood my professor.

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    $\begingroup$ You forgot protection/deprotection of amino group. $\endgroup$ – Mithoron Jul 9 at 23:24
  • $\begingroup$ I am sure you can come up with a specific title. $\endgroup$ – Nilay Ghosh Jul 10 at 16:21
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The steps for conversion of Benzene to 1,3-dichloro-5-(propan-2-yl)benzene are shown below (Scheme).

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  • $\begingroup$ A possible improvement would be to use a large protecting group like pivaloyl instead of acetyl. This should more effectively prevent ortho alkylation. Then again, it's probably also more annoying to deprotect. There's probably a good intermediate size group. $\endgroup$ – Zhe Jul 10 at 18:03
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You have to protect the amino group because the amino group is so activating that it is hard to stop multiple substitutions from occurring. By reacting it with the anhydride, the lone pair on the amino group gets delocalized due to conjugation and is therefore less available to the ring, making it easier for one addition. However, it seems that you want the chlorines ortho to the amino group, since it can't go para due to the isopropyl. So multiple substitutions shouldn't matter.

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