Chemical Forums
Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: Xboss on October 26, 2009, 03:18:23 PM
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The reaction is
1,4-Dioxane
R-SH + Cl.SO2-Ar-NHAc -----------> R-S-SO2-Ar-NHAc + HCl
0.1M 0.2M Pyridine
The solvent was 1,4-Dioxane & Pyridine as base... i got pyridinium chloride as the precipitatig product which was filtered and the solvent then concentrated to get the thiosulfonate aka sulfonyl sulfide
The sulfonyl chloride is taken double molar quantity than the Thiol other wise the product is a disulfide ... R-S-S-Ar-NHAc
can't figure out the mechanism .. have devoured almost all articles on JACS as well as Org. Letters but still clueless
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This is just a total guess, but you have a secondary amine in there.
Maybe the amine attacks the sulfonyl group intramolecularly, then the Cl- gets kicked off as a leaving group and the N ends up with a positive charge.
The pyridine then strips off the H from the postively charged N, thus generating your pyridinium chloride salt.
Then the thiol attacks the the sufonyl group, the N turns into the leaving group and leaves with a negative charge.
The 1,4-Dioxane then comes in and pulls the H off of from the thiol.
Then the amino group which is at this point is negatively charged acts as a base and pulls the H off of the 1,4-dioxane.
Wish I had the software to draw it out for you, but I am on Linux and they don't have anything good like ChemDraw for Linux.
Anyway, like I said it was just a total guess, but the main point is that maybe there is some sort of intramolecular attack going on?
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The reaction is
1,4-Dioxane
R-SH + Cl.SO2-Ar-NHAc -----------> R-S-SO2-Ar-NHAc + HCl
0.1M 0.2M Pyridine
The solvent was 1,4-Dioxane & Pyridine as base... i got pyridinium chloride as the precipitatig product which was filtered and the solvent then concentrated to get the thiosulfonate aka sulfonyl sulfide
The sulfonyl chloride is taken double molar quantity than the Thiol other wise the product is a disulfide ... R-S-S-Ar-NHAc
can't figure out the mechanism .. have devoured almost all articles on JACS as well as Org. Letters but still clueless
Maybe I've missed something here, but isn't it obvious? How would you form a sulfonate ester from a sulfonyl chloride? What is the mechanism of that reaction?
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Maybe I've missed something here, but isn't it obvious? How would you form a sulfonate ester from a sulfonyl chloride? What is the mechanism of that reaction?
lol, you're right. All that gibber-jabber I posted earlier is total nonsense.