[omegasynthesis999]

How can I synthesize, starting from Benzene a molecule that has a -COOH substiuted at the 1 position, a -NO2 group substituted at the 2 position and a propyl group at the 4 position?

I can't figure out which reactions to use. The main problem is getting the -COOH. I can put on a CH3 group via Friedel-Craft and a propyl using acylation (converted into a propyl via Clemmenson reduction). I can then proceed to add the -NO2 group. However if I oxidize with KMnO4, I will end up getting -COOH at both of the alkyl positions. Is there a way to get around this? Or perhaps is there another more effective pathway.

Thanks

[macman104]

Save the clemmenson until after you oxidize the methyl group.  The oxidation of the aliphatic groups to COOH requires a benzylic hydrogen which the acylated propyl group does not have.  And the clemmensen reduction should not affect the COOH group either.

[omegasynthesis999]

Thats not true. An acylated propyl group can be oxidized with hot alkaline KMnO4 to a -COOH group as well. Any alkenyl, alkynyl or acyl groups will be oxidized to -COOH. This is one of the troubles I am having with my synthesis.

[macman104]

Thats not true. An acylated propyl group can be oxidized with hot alkaline KMnO4 to a -COOH group as well. Any alkenyl, alkynyl or acyl groups will be oxidized to -COOH. This is one of the troubles I am having with my synthesis.

Really?  I was pretty sure I read that the oxidation with the hot alkaline KMnO4 requires a benzylic hydrogen...

[sjb]

Another stab

Bromobenzene -> p-propionylphenyl bromide (F/C, separate from o-isomer -> nitrate -> Reduce the ketone (not sure if Clemmensen Reduction woud also affect the nitro group here, maybe Wolff-Kishner instead)-> metallate the bromide and add dry CO_2(g) ?

S

[omegasynthesis999]

Haven't learned about metallate or Wolff-Kishner. But yes, the clemmenson would affect the NO2 and turn it into an NH2.