Synthesis of 3,4,5-trimethoxybenzaldehyde cyanohydrin acetate and subsequent reduction thereof with Pd/H2 @ 1atm is described in
https://www.thevespiary.org/rhodium/Rhodium/chemistry/mescalyptus.html
Yield of acetylated mandelonitrile is only ~66% from the benzaldehyde. It involves the use of KCN.
In Ref[1] O-acetyl-mandelonitrile is prepared in 90% yield at ambient temp in 1 hour from benzaldehyde, 2-oxo-propionitrile and aq. K
2CO
3 soln. in acetonitrile.
No, I have not read the article. Yes, I want to know what it says,too.
Now, what is 2-oxo-propionitrile and how is it made ?
I hope you can guess it's structure from the following little ascii drawing:
H3C-C=O
\
CN
There must be a hundred ways to make it.
[2] Wacker oxidation of acrylonitrile @ 30°C
[3] from KCN and acetylbromide
Dehydration of 2-oxo-propionaldehyde oxime
[4] with P2O5 in CS2
[5] with acetylchloride
Of these I think 2-oxo-propionaldehyde oxime holds the most promise for it can be prepared from acetone and
[6]ethylnitrite (74% - 45°C - 60min) [looks somewhat familiar,eh ?]
[7]methylnitrite / HCl
[8]AcOH / NaNO2 at 0°C
[9]N2CO3 / Na2[Fe(CN)5NO] (sodium nitroprusside)
There are tons more ways out there but one thing sticks out especially: in
Patent US2980708
they describe the thermal rearrangement of easily made oxime-acetate
to nitrile by dry distillation. They use the corresponding epoxialdoximes
(and produce the epoxinitriles which,in turn, can also be used to make the oxonitriles) but it might as well work on the oxy-aldoxime, too.
comments eagerly awaited
BTW: you may encounter the use of Ac
2O here and there if you're doing research into this topic, besides it's quite useful generally, may it be for the production of AcBr from Ac
2O and HBr, which may sound like the wrong way but have a look at
Patent US1430304
where Henry Dryefuss demonstrates how to make Ac
2O by simpy heating a mix of Na
2S
2O
7 and NaOAc. It has once been mentioned before by PolytheneSam but maybe wasn't recognized ??
[1] Okimoto, Mitsuhiro; Chiba, Toshiro; SYNTBF; Synthesis; EN; 10; 1996; 1188-1190.
[2] Smidt; Sieber; ANCEAD; Angew.Chem.; 71; 1959; 626.
[3] Mukherjee, Jogeshwar; Rogers, Janice I.; Khalifah, Raja G.; Everett, Grover W.; JACSAT; J.Amer.Chem.Soc.; EN; 109; 23; 1987; 7232-7233
[4] Scholl; MOCMB7; Monatsh.Chem.; 39; 1918; 238.
[5] Claisen; Manasse; CHBEAM; Chem.Ber.; 20; 1887; 2196
[6] Tajbakhsh, M.; Bakooie, H.; Ghassemzadeh, M.; Beheshtiha, Y. Sh.; Heravi, M. M.; IJSBDB; Indian J.Chem.Sect.B; EN; 40; 12; 2001; 1232 - 1233
[7] Slater; JCSOA9; J.Chem.Soc.; 117; 1920; 589.
[8] Kuester; HSZPAZ; Hoppe-Seyler's Z.Physiol.Chem.; 155; 1926; 180.
[9] Schmidt; ARPMAS; Arch.Pharm.(Weinheim Ger.); 250; 1912
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psyloxy--