Niklas
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Some quick notes on the preparation of lead(IV)-acetate
Lead(IV)-acetate is a useful oxidant in both inorganic and organic chemistry, me being interested in it to use in a Kochi-Decarboxylation in
particular to make iodocubane (I‘ve actually already done this reaction and it worked beautifully, once I have the NMR I‘ll post its preparation
in my cubane thread).
It’s preparation is achieved by simple reaction of lead(II,IV)-oxide with glacial acetic acid with acetic anhydride added to react with the water
produced to prevent hydrolysis of the acetate (https://onlinelibrary.wiley.com/doi/10.1002/9780470132326.ch...).
(Only work with lead if you have a proper way to dispose of heavy metal waste)
A 250 ml wide-neck erlenmeyer flask, containing a 3,5 cm cylindrical stirbar and an internal thermometer, was charged with 108 g of glacial acetic
acid and 36 g of acetic anhydride (353 mmol). With good stirring 60 g of lead(II,IV)-oxide (87,5 mmol) (Note 1) were added in spatulas gradually at a
rate so the powder doesn’t cake up, and the resulting orange suspension warmed on the hotplate to a temperature of 60 °C (Note 2) until all the
orange color had disappeared, taking a couple minutes, resulting in a pinkish suspension of the product. Things were left to cool over night (Note 3),
collected by vacuum filtration on a 10 cm Büchner funnel, washed with some glacial acetic acid and a little bit of n-pentane (Note 4), and finally
dried under vacuum. From this 25,3 g (62,5% yield, 77,3% lit.) of light pink needles were collected, quickly turning a brown color on exposure to
humid air, and are therefore stored under argon.
Note 1: It seems logical to assume that using lead(IV)-oxide directly should equally work in this preparation, however when attempting this the
mixture had to be heated to 100 °C for a couple of days to achieve completion of the reaction resulting in a gel like precipitate which was
impossible to filter.
Note 2: In the procedure the heating is described as optional as the addition is described to already be exothermic, I however never noticed an
increase of more than 5 °C.
Note 3: When things were filtered just shortly after reaching room temperature the precipitate partly had a gel-like consistency, causing the
filtration to be a lot slower and a whole lot more annoying.
Note 4: By passing chlorine through the mother liquors the byproduct lead(II)-acetate could be oxidized to more lead(IV)-acetate, as I got more then
sufficient material for my immediate applications and it’s best prepared fresh to avoid hydrolysis I didn’t bother doing that though.
Fig.1: Suspension of the lead(II,IV)-oxide
Fig.2: The collected product
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Mabus
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Great job! I think this is the first time I've seen a photo of the actual compound, looks quite interesting, reminds me of manganese sulfate with that
pink coloring.
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woelen
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Nice synthesis indeed. Good to see that it is possible to make such a special compound in an amateur lab.
I think that the pink/orange coloring is due to very fine particles of Pb3O4, which were not dissolved. Another source of the color may be from slight
hydrolysis of the product, which also may contain a little lead(II). The hydrolysis then may lead to formation of Pb3O4.
I myself have a commercial sample of 50 grams of lead(IV) acetate. It is a snow white solid, which easily dissolves in cold water and fairly quickly
(a few minutes) hydrolyzes, giving a dark brown very finely powdered precipitate of PbO2.
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Maui3
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Good job. Looking forward to the iodocubane post :-)
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chempyre235
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Great work, as always.
Despite its toxicity, I'm honestly surprised that this compound hasn't seen more use in an amateur setting. It seems to be useful for oxidations,
dehydrogenation of hydrazine and derivatives (to make diazomethane derivatives), and as an acetylating agent in certain cases. It seems to be able to
replace ozonolysis is special cases, as well. It's also used in the Kochi reaction, which decarboxylates organic acids to alkyl halides.
https://orgsyn.org/demo.aspx?prep=CV6P0056
https://orgsyn.org/demo.aspx?prep=CV6P0161
https://pubs.acs.org/doi/abs/10.1021/jo00912a019
https://academic.oup.com/bcsj/article-abstract/9/1/8/7380367...
I too, am anticipating the iodocubane post.
[Edited on 10/15/2025 by chempyre235]
"However beautiful the strategy, you should occasionally look at the results." -Winston Churchill
"I weep at the sight of flaming acetic anhydride." -@Madscientist
"...the elements shall melt with fervent heat..." -2 Peter 3:10
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