bmays
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Tetraethyl lead synthysis with lithium lead alloy?
4NaPb + 4CH3CH2Cl → (CH3CH2)4Pb + 4NaCl + 3Pb
I see no reason the reaction will not proceed with LiPb substituted for NaPb. Am i right? I am thinking the alloy should be 1:1 by molarity.
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Metacelsus
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Why not 4:1?
Na4Pb + 4 EtCl -> Pb(Et)4 + 4 NaCl
http://pubs.acs.org/doi/full/10.1021/om030621b
(It contains a procedure for Pb(Et)4 using 4:1 Na-Pb. This is with EtBr; with EtCl it says 1:1 is best)
Anyway, Wikipedia says that it is possible with Li:
https://en.wikipedia.org/wiki/Tetraethyllead#Synthesis_and_p...
"A process with lithium was developed, but never put into practice."
You probably want to use EtBr instead of EtCl, which is a gas at STP.
https://en.wikipedia.org/wiki/Chloroethane
https://en.wikipedia.org/wiki/Bromoethane
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UnintentionalChaos
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I would strongly advise against this synthesis. TEL is volatile, highly lipophilic, and neurotoxic with a frighteningly low boiling point of only
84C. It's hardly a surprise that it killed something like 17 workers shortly after it began being manufactured on a large scale as an antiknock agent
and likely poisoned quite a few more.
If you are dead set on making a stable organometallic, consider something like tetraphenyltin. While toxic and lipophilic, it is a much more easily
manipulated solid with a high boiling point. The synthesis does not require a bucket of sodium alloy and alkyl halides. SnI4 can be prepared in a
flask from the elements (synthesis detailed elsewhere). A solution of this is added to PhMgBr solution (prepared like any standard grignard reagent)
in the right ratio and the product is worked up.
Department of Redundancy Department - Now with paperwork!
'In organic synthesis, we call decomposition products "crap", however this is not a IUPAC approved nomenclature.' -Nicodem
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