Sciencemadness Discussion Board

Zr IV organometal complex: structure explained?

blogfast25 - 11-6-2013 at 04:17


Does anyone know the structure of a compound called:

Zirconium IV bis octanolato, cyclo (dioctyl) pyrophosphate-O,O

A coupling agent.

watson.fawkes - 11-6-2013 at 06:03

Quote: Originally posted by blogfast25  
Zirconium IV bis octanolato, cyclo (dioctyl) pyrophosphate-O,O
Looks to have been manufactured by Kenrich Petrochemicals, which has a whole line of coupling agents that look like that class of chemical. I'd recommend calling them.

Also see this patent application.

Added: It's Kenrich product "KZ OPPR". The octane group is 2-ethylhexane.

[Edited on 2013-6-11 by watson.fawkes]

blogfast25 - 11-6-2013 at 11:35

I know, Watson, I found that Kenrich range yesterday. But it doesn't tell you the structural formula. Cold calling these people could take some nerve, they don't tend to be quite responsive to non-commercial enquiries. Still, might have to give that a try...

The 'four page brief overview' does shed some light on these strange animals:

http://www.4kenrich.com/Content/home-page/technical-informat...

[Edited on 11-6-2013 by blogfast25]

KrysHalide - 11-6-2013 at 13:51

I would say a Zr IV metal center complexed with two octanolate ligands (RO-) and a dialkyl pyrophosphate ligand (RO-PO(O-)-O-PO(O-)-OR, linked to the metallic center by the O-

sorry i don't have a molecule drawing software at hand, but octanoloxyphosphate ligands are more or less common with zirconium, well I have already seen some, so by "coupling" two such ligand to a pyrophosphate ligand should be possible.

KrysHalide - 11-6-2013 at 13:53

Have a look at this compound: a alkoxy ligand and three alkylphosphates ligand.. should give you the picture

http://www.chemicalbook.com/ProdSupplierGWCB2129279_EN.htm

AndersHoveland - 11-6-2013 at 15:42

Quote: Originally posted by KrysHalide  
Have a look at this compound: a alkoxy ligand and three alkylphosphates ligand.. should give you the picture

Some of these databases get the structure wrong. That is certainly the case with "manganese(III) acetate", because often times the common chemical name is not entirely accurate, and the structure is actually much more complex with ligand bonding and delocalization. I am not sure if this case, but am just suggesting caution be used with some of these specific metal ligand compounds.

watson.fawkes - 11-6-2013 at 16:44

Quote: Originally posted by blogfast25  
The 'four page brief overview' does shed some light on these strange animals:

http://www.4kenrich.com/Content/home-page/technical-informat...
The patent on that page, No. 4,277,415, has a bit of structure diagram in it. It's for Ti, but the Zr ion seems to be interchangeable for many of these. Of particular note is a formula with subscripts 'c' and '4-c'; these are the number of central ligand positions.

Best I can tell, that notation means that the pyrophosphate is acting as a bidentate ligand, bound through an O on each end. So there's one (modified) cyclo-pyrophosphate, taking up two ligand positions to the Zr and thus forming a ring, and there are two octanolate goups, taking up the other two ligand positions.

Compare their product "KR OPP2", which has two cyclo-pyrophosphate groups and no other ligands, again totalling four central ligand positions.


blogfast25 - 12-6-2013 at 03:32

Thanks KrysHalide and Watson.

I now know enough about the structure to conclude it's probably very easy to hydrolyse to Zr(OH)4 at RT, using a strong alkali and that's what I wanted to know.

It would appear that the alkanolate side is designed to couple the Zr, Ti to substrates with lots of free -OH groups (in this case an uncured polyester), while the other side provides 'compatibility' with another substrate to be used as coating of the treated polyester. All this brought to you from the slightly murky world of 'bonding agents', 'coupling agents' and 'polymer compatibilisers'...

[Edited on 12-6-2013 by blogfast25]

KrysHalide - 12-6-2013 at 04:07

Pardon my curiosity, but what were asking this for? Do you plan on retreiving Zr(OH)4 from this material? That seems like a bit of a waste! Or something else?

blogfast25 - 12-6-2013 at 13:12

Quote: Originally posted by KrysHalide  
Pardon my curiosity, but what were asking this for? Or something else?


Determination (semi-quantitative) of such a compound on a surface treated with it.