Sciencemadness Discussion Board

diol to oxo conversion

chemrox - 19-8-2011 at 09:38

I have a large quantity of 1,1 cyclopentane diol and I want to make some of it into cyclopentanone. I've looked everywhere I can think of for this conversion with no luck. I tried a standard oxidation with KMnO4 and ended up with a purple mess that smelled like old gym socks. A pointer as to where I might find the information would be appreciated. Thanks, CRX

smuv - 19-8-2011 at 20:15

1,1-cyclopentanediol...so the hydrate of cyclophentanone? typo?


Late edit: cyclopentanone not cyclophentanone (whatever that is)

[Edited on 8-20-2011 by smuv]

ThatchemistKid - 20-8-2011 at 19:25

This could be a shot in the dark but.. if you subjected it to dehydration conditions you could make a double bond between carbons one and two or one and five (doesnt matter) enol keto tautomerization leads to cyclopentanone. I think I similar method is used to make acetyl aldehyde from ethylene glycol under certain conditions.. granted though the hydroxyl groups are on different carbons in that case.

ThatchemistKid - 20-8-2011 at 19:27

actually wait..yes the hydrate of cyclopentaone did you mean 1,2 cyclopentane diol, that is what I thought your post said when I first read it? ..the above mentioned method could still work in that case.

not_important - 20-8-2011 at 20:14

If it is the 1,1 diol then it's a hydrate. Dump into tolune and azetrope off the water.

If it's the 1,2 diol then the acid catalysed pinacol-typr rearrangement (with hydrogen migrating) will give the ketone.

Oxidation would give the diketone and/or ring opening to dicarboxilic acids and so on.


http://jjc.yu.edu.jo/Issues/Vol4No3PDF/05galley%20proof%20of...


http://en.wikipedia.org/wiki/Pinacol_rearrangement


chemrox - 24-8-2011 at 12:54

thanks-it is the 1,1 I'll try the azeotrope.. it wouldn't be bad to have it in toluene anyway