Monday, September 05, 2011

Does this sulphur compound even exist?

Sulfurs are difficult; they do all sorts of wicked bonding. I was told QM approaches don't handle them easily either. They stink.

Cheminformatics models atoms, so sulfurs too. With the richer chemistry of sulfurs, come more atom types to model their behavior. The CDK project is currently discussing atom types for sulfur, and one is found in this compound (C8H16S):
ChemSpider has this compound deprecated, and a search will not find it. PubChem seems to have a stereoisomer (thanx to chemlynx for noting), but the question is, has this compound or one of its stereoisomers ever been found in nature or synthesized. Cheminformatics is solved, but answering this question is near to impossible, or really expensive at least. Does this compound exist? What is its melting point? What is its C/H/S NMR spectrum? Does it stink too? Does it have a crystal structure? What is the logP, the pKa? How is it synthesized? Can the structure even exist?

I will check tomorrow of my medical university has access to proprietary databases that can answer this question. I know there are some tools around to go searches on the world wide web. Please let me know what they come up with!


  1. Oddly, if you search on chemspider for a dimethyl-thiopyranium [ C1C(C)CCS(C)C1 ] substructure, you get some compounds with an [S+] and some without, where some have stereo and some don't.

  2. A quick search of Reaxys shows one citation for this compound. A patent from Avecia.

    US Patent: US6559323 B1, 2003 ;

    However in a very quick skim of the structures I couldn't spot it.

  3. Chris, I had a look at that patent via SureChem, and the list of extracted structures shows similar compounds, but not the one here, confirming your observation.

  4. Looking at the particular structure denoted here, I'm fairly certain that this species with a hydrogen attached to the sulfur does not exist. Thinking about the possible routes that could be used to generate this structure I can't see a way that this could be chemically synthesised.

    I'm also sceptical that it is possible to generate a tetra alkyl sulfur species. It is possible to synthesis a sulfur ylide but this should really be considered as a charge separated zwitterion, and is essentially the same as a sulfoxide.