clearly_not_atara
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HVZ bromination with S instead of P?
It’s well-known that S + Br2 converts many acids to their anhydrides. The rxn byproduct HBr can react again to convert anhydrides to acyl bromides
which are enolizable. Overall, this resembles the HVZ reaction:
http://en.wikipedia.org/wiki/Hell-Volhard-Zelinsky_halogenat...
S is much more available than P which is the usual catalyst for this reaction (forming PBr3 in situ). P has the practical advantage of not producing
SO2 efflux, but S is much cheaper in practice. So is this a possible poor man’s HVZ?
Another possibility: could succinic or phthalic anhydrides be used?
[Edited on 15-9-2019 by clearly_not_atara]
[Edited on 15-9-2019 by clearly_not_atara]
[Edited on 04-20-1969 by clearly_not_atara]
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Pumukli
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I heard about S for chlorinating acetic acid but never got to the experimental phase. :-)
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DavidJR
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No idea but I bet if you use sulphur it will absolutely stink...
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12thealchemist
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You wouldn't suffer from organosulphur byproducts unless a very unlikely reaction mechanism took place - at no point is a P-C bond formed in the
mechanism, so no S-C bond would form. You would have to watch out for sulphur oxides though
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Loptr
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Quote: Originally posted by 12thealchemist  |
You wouldn't suffer from organosulphur byproducts unless a very unlikely reaction mechanism took place - at no point is a P-C bond formed in the
mechanism, so no S-C bond would form. You would have to watch out for sulphur oxides though |
I believe the thought is that H2S would be formed during the course of the reactions and also most likely during any quench with water. That is pretty
smelly.
[Edited on 17-9-2019 by Loptr]
"Question everything generally thought to be obvious." - Dieter Rams
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