Easy Aromatic Iodination Reference

[foxy2]

It is the second article listed.

http://www.kcsnet.or.kr/publi/bul/bu98n4/bu98n4.html#bu98n4-2

Or here is the link

http://www.kcsnet.or.kr/publi/bul/bu98n4/400.pdf

Do Your Part To Win The War

[hest]

My ekspirience with this method is not that greath. Did it on 1,4-dimethoxybenzene, ended up with the non iodide, mono-iodide and di-iodide in equal amounts.  

[Rhodium]

I guess that ring is too activated (two positions para to methoxy). Try it on 2,5-dimethoxybezaldehyde, and let it react long enough for the only substitutable position to be fully iodinated. That procedure should not produce any side-reactions.

The procedure is archived on my page under aromatic halogenation in the Phenethylamine section.

[hest]

You are prob. right.
When I iodinate 1,4-DMB i mix one mole 1,4-DMB one mole I2 and one mole AgNO3 in methanol, let it stear for 6-8 hours and work up. Works greath (it also works on 2,5-dmba yeald app.80%)

[Rhodium]

AgNO3 is not necessary, and probably makes the iodination even more powerful. The reference uses NaNO3 with good results, which is orders of magnitude cheaper.

[hest]

Yep, but AgNO3 works cleaner, and you can recycle the AgI to AgNO3 and use it again.
I'v tryet som diff. routhes to the iodide. Just iodine wont work, Iodine and H2O2 and H2SO4 did'nt work either.
ICl works ok, but you gets some off the Cl product too.
And by the way, it is werye small amounts off KNO3 you have to add in that article, but i guess too much wont doo annye harm.
But i guess its rather academic. Why not just brominate if you want to turn 1,4 to the more fun aldehyde (via Grinard).