Sciencemadness Discussion Board

a-iodination

dextro88 - 28-6-2020 at 18:13

Im thinking of a-iodination via CuO/I2/Methanol method,
the patent says eq. molar amaunts of I2 to Ketone and CuO shoud be used,
as the CuO will reoxidize the formed HI back into I2, woundnt 0,5 I2 to 1 mole CuO to be the optimal reaction conditions, as i dont understand how they dont get diiodinated product using such big quantities Iodine, and as i understand the reaction speed can be determined by the color change of the coper dioxide to the red/brown coper oxide and water and I2 will be reaction byproducts, im thinkink how to remove the iodine to have a clean ketone without to interfere with the a-iodine atom.

Boffis - 29-6-2020 at 00:50

What patent?

dextro88 - 29-6-2020 at 01:21

https://sci-hub.tw/10.1055/s-2007-983880,
they state all from 1-0.7 eq I2 works in 99% yields too but above 0.7 eq they tell its reducing the yield, since equimolar HI to the iodine consumed will be produced and latter it will be catalyzed back to I2, so i dont see the reason to even use more than 0.5 eq. I2 but i dont have TLC nor any analytical machine to see how the reaction is going.

[Edited on 29-6-2020 by dextro88]

draculic acid69 - 29-6-2020 at 01:40

What about refluxing I2,hno3 and the ketone? Will it work the same as it will on a benzene ring or will it just result in crap?

dextro88 - 29-6-2020 at 02:36

hmm maybe you are confused with aromatic iodination, the proposed mechanism here is a-iodination of the carbon chain of a ketone