chornedsnorkack - 8-6-2023 at 09:36
Cyanoform was for over a century a notoriously missing substance. While cyanoform salts could be produced and production of cyanoform from its salts
was tried already by 1896 - what are the easiest synthetic routes to sodium cyanoformide? - it always decomposed on separation.
Cyanoform was finally separated in 2015. And that was duh. Cold hydrofluoric acid. Decomposes at -40 C. Handling cold acids should have been a
standard technology. A 1960 preparative inorganic chemistry includes synthesis for thiocyanic acid, that decomposes at -85 C.
What other cold acids are good to produce cyanoform?(Fluorosulphonic? Chlorosulphonic? Hydrochloric?)
Another related substance, for which I could not figure out a name which would return consistent useful references is HC(COOH)3. What is it called?
And other substances in between - HCCN(COOH)2 and HCCOOH(CN)2. How are they called? How labile are they?
unionised - 8-6-2023 at 13:52
I don't know if methanetricarboxylic acid exists, but you can buy its ester.
https://www.alfa.com/en/catalog/L08356/
Getting back to cyanoform, the synthesis starts with sodium tricyanomethanide.
But does anyone know how you get that?
wg48temp9 - 10-6-2023 at 15:29
I, too, was curious how sodium tricyanomethanide could be made. I hypothesised reacting chloroform with sodium cyanide in alkaline condition to
deprotonate the tricyanomethanide as soon as it forms.
I searched for a procedure and found a patent that reacts malononitrile with cyanogen chloride. Melononitrile can be prepared by reacting cyanogen
chloride with acetonitrile. I guess you could go directly from actonitrile to sodium tricyanomethanide.
Here is the patent:
Attachment: metal-tricyanomethanides-EP2674416A1.pdf (208kB)
This file has been downloaded 135 times
Please note this procedure is potentially very dangerous, I don’t recommend anybody try it.
[Edited on 6/10/2023 by wg48temp9]