Jump to content

Talk:Lithium bis(trimethylsilyl)amide

Page contents not supported in other languages.
From Wikipedia, the free encyclopedia

Untitled

[edit]

Purified by vacuum distillation? Seems pretty impractical... Eugene Kwan (talk) 13:35, 29 October 2010 (UTC)[reply]

Solvent free in solution?

[edit]

I'm confused by the statement "When solvent-free, this compound is dimeric in solution". Does this mean that its dimeric in non-coordination solvents (e.g. hexane, toluene)? Or is is just a typo? I'd fix this myself but the reference is in German. Project Osprey (talk) 14:08, 30 January 2013 (UTC)[reply]

Now sorted. Project Osprey (talk) 21:50, 30 June 2013 (UTC)[reply]
Coincidentally (or by ESP), I rewrote and "re-imaged" this article so that readers dont come away thinking that this stuff is ionic. I found crystal structures in CSD. The monomer and dimer are probably best depicted --Smokefoot (talk) 13:21, 1 July 2013 (UTC)with ligands since bent 2-coordinate and terminal Li are unlikely. Comments or suggestions welcome.--Smokefoot (talk) 21:59, 30 June 2013 (UTC)[reply]
  • Tricky one this. I can see why you're going for the trimer - left to its own devices its what you get. Part of me still thinks the monomer should be shown in the chembox though; as it matches the stated names, formula and mole-weight. Looking across the series LiHMDS, NaHMDS and KHMDS are now all shown as having different structures, so whatever gets decided here should probably get rolled-out.Project Osprey (talk) 22:51, 30 June 2013 (UTC)[reply]
Yep, it is tricky. In the chembox for butyllithium, a variety of structures are shown, beginning with the monomer, which is irrelevant to chemists but at least matches the name. I guess a similar gallery approach would be the way to achieve some consensus and convey the trickiness for the HMDS species. It looks like KHMDS exists (at least in one form) as the unsolvated dimer, and NaHMDS is trimeric. We could show the monomeric representations, but probably not as ions, but covalent.--Smokefoot (talk) 23:10, 30 June 2013 (UTC)[reply]
  • What you’ve done with NaHMDS seems best to me; a few images in the chembox with a section explaining what going on. I have a proposal for the structure section - If you could generate one of those nice ball and stick models of the THF coordinated monomer; I’ll tweak my ‘aggregation equilibrium’ image to show solvent. A bit of time spent arraigning images would give us a nice visual depiction of the overall process – dunno if you think that’s worthwhile or not? Project Osprey (talk) 08:43, 1 July 2013 (UTC)[reply]
OK, I will look for an Na derivative with THF or ether tonight or tomorrow night. A related recommendation might be to change your ChemDraw File:LiHMDS aggregation.png to include solvent coordination at the dimer and monomer levels. Real world takes over for a while for me soon though, precluding larger projects like this one. Later.--Smokefoot (talk) 13:21, 1 July 2013 (UTC)[reply]
Solvated Li monomer it will be... in a day or three. Cheers, --Smokefoot (talk) 03:24, 2 July 2013 (UTC)[reply]
Took me a while, but I just found the tmeda complex. --Smokefoot (talk) 00:10, 4 July 2013 (UTC)[reply]