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Suggest a synthetic route to m-nitrotoluene, starting from benzene.

The conversion can be achieved in two ways:

$\hspace{10 mm}$Route 1

or:

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However, the first route is not possible as the Friedel-Crafts reaction does not yield a meta-substituted product. Why is that so?

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    $\begingroup$ Hmm, I don't like second reaction either, you have proof it would work? $\endgroup$ – Mithoron Dec 22 '15 at 22:28
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    $\begingroup$ Also, I don't believe Na will leave that nitro group intact. $\endgroup$ – Ivan Neretin Dec 23 '15 at 6:35
  • $\begingroup$ The use of a methyl halide does not seem feasible to me, as it suggests that the electrophile would be a methyl carbocation, which does not form in practicality. I would imagine otherwise that $\endgroup$ – Sterling Cavanaugh Apr 30 at 2:39
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The nitro group is so deactivating that yields are really poor for Friedel-Crafts reactions with nitrobenzene; not even the meta-substituted product is found in good yield. In fact, nitrobenzene is actually used as a solvent in Friedel-Crafts reactions.

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    $\begingroup$ Agreed. Most undergraduate organic chemistry texts come with a big disclaimer that Friedel-Crafts reactions work poorly on deactivated rings. I would love to see a link or reference for the use of nitrobenzene as a solvent for FC reactions. It would really solidify this answer. $\endgroup$ – Ben Norris Dec 22 '15 at 18:14
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    $\begingroup$ @BenNorris onlinelibrary.wiley.com/doi/10.1002/bscb.19660750903/abstract $\endgroup$ – ShankRam Feb 8 '16 at 2:15

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