[UChu]

Hi,

I am using solid state chemistry (A. Hajipour 2005) to nitrate phenyl-propyl bromide and I kept getting ortho and para-nitro.  I need to ask if anyone have experiences in separating these two isomers and can give me some tips.  I've tried column chromatography but both products came out at the same time.  I've also tried to separate the two isomers on TLC, however, they migrate so close together and become a huge band instead of two separate bands.  I've tried finding a solvent system but have failed to find one good enough to separate the two.

I'd appreciate the help.

[lavoisier]

Sorry, maybe it's me, but I can't see what you mean with phenyl-propyl bromide. Could you please provide a IUPAC name or a SMILES?

[UChu]

I am nitrating 1-bromo-3-phenyl-propane into 1-bromo-3-para-nitrophenyl-propane (I think this is the right name), but I am getting both the ortho as well as the para product.  I need help separating the two.

Thanks.

[Dude]

I haven't looked up the details of nitration for several years, but my recollection with aromatic electrophilic substitution is that you can sometimes minimize undesirable compounds by lowering the reaction temperature.  That would be my first approach.  If you can't minimize the formation of the ortho isomer, perhaps recrystallization using a non-polar solvent  You might find that only the para isomer has a mp above room temperature.

[Dude]

http://www.calvin.edu/~dav4/Documents/jo025508u_s1.pdf

Here's a wet chemistry synthesis for reference with the IUPAC name.

[UChu]

The compound I synthesized is not a solid therefore I cannot recrystallize it, but I'll check out the website.

Thanks

[UChu]

A chemist in the lab had tried this procedure and caused an explosion that scarred his face for 3 months therefore he suggested the solid state chemistry procedure I described above.  He had gone back to Iran and so I need outside help. Any other suggestions?