better question is, with what degree of difficulty, can one grow large crystals of it? this one is also on my colors and crystals list, though ive
never given much serious thought to it, its quite low and iirc the indirect synthesis deals with some issues if you dont want to use acetic anhydride
or sodium metal.
conveniently however, two new methods for producing ethoxide have popped up here in the forum. well actually 3.
ethoxide can be produced by either, adding enough, relatively dry hydroxide, to relatively dry ethanol, in a column, that they seperate into a slurry,
brine and organic phase, the organic phase, will be of some concentration depending on the equillibrium between ethoxide - hydroxide - water and
ethanol, though supposedly its virtually nil water and theres just a bit of hydroxide dissolved.
the other method involves distilling a solution of hydroxide and ethanol to remove water, ideally azeotropically, but this is an incredibly taxing
solution to reflux/distill, so if it cant be done quickly, to the same effect under vacuum, or otherwise effectively, you end up with damaged glass
and silicate contaminated product.
lastly, a compromise method, supposedly hydroxide can be eliminated by the addition of ethyl acetate since the hydrolysis that occurs doesnt release
water, water only forms from the reaction of ethanol and hydroxide, and, the hydroxide OH group winds up on the ethanol rather than turning into
water.
In all methods as well acetone can be added to precipitate the ethoxide, though, it seems like there is probably a way to 1-pot model the reaction
since once you have ethoxide in some form, only acetone and ethyl acetate are needed at that point to both purify/isolate it, or, convert it to the
acetylacetonate.
an issue with sodium acetate forming though is, its supposedly in a very inconvenient, gummy state that isnt easily filtered.
If lithium could be directly substituted though, which i think it can i just havent seen it directly refferenced, thats easy enough to get. the yields
from lithium in principle should be something like 3x higher if the reaction efficiency is the same. 1 mol of sodium makes around a mol of
acetylacetone, so 6g of lithium adds up to 80g of acetylacetone based on the orgsyn procedure using sodium. Yields are said to drop terribly with
lower quality reagents, or likely, the presence of water just has a catastrophic effect. but a pack of lithium AAs should provide more than enough
acetylacetone to supply the neccesary bulk mass for growing large crystals
I rambled a bit there, so now the only matter is, exactly how does one grow large copper crystals?
based on https://doi.org/10.1002/anie.201806431 slow evaporation of methanoic solution results in the formation of crystals, though its not clear at what
scale, this study can/does investigate properties of micro scale crystals.
Atomic Resolution of Structural Changes in Elastic Crystals, https://doi.org/10.1038/nchem.2848
describes the preparation from copper nitrate briefly, and that crystals of some size were grown from chloroform, but again this study basically
occurs under a microscope.
also note; the supporting material for the above contained this video of what is claimed to be a singular crystal, at least by my interpretation,
being tied into a knot.
https://static-content.springer.com/esm/art%3A10.1038%2Fnche...
it always pays to check a studies "supplementary information", its never paywalled, and sometimes also includes the synthesis/workup procedure in
studies dealing with new/novel methods or substances entirely, but focus more on analysis than synthesis.
Anyway, it would be safe to assume that, a knottable crystal could be formed through the use of chloroform, with any potential nitrate contaminants
present.
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