C.2, the preparation of 5-dimethoxy-phenylethylamine
Patent CN101311162B
" The reflux water-dividing device is being housed, add alpha-amino group-2 in the 1000ml three-necked bottle of thermometer and magnetic stirring
apparatus, 5-dimethoxy-acetophenone (19.5g, 0.1mol), potassium hydroxide (33.6g, 0.6mol), glycol ether (240ml) and concentration are 80% hydrazine
hydrate (38ml, about 0.6mol), stirring and refluxing is divided the water reaction, until the water of telling above theoretical amount, continue
again to reflux 2 hours, have about 18 hours altogether, reaction finishes, reaction mixture is poured in the frozen water after being cooled to room
temperature, and mixed solution extracts with ethyl acetate (100ml * 3), separatory, the ethyl acetate layer anhydrous sodium sulfate drying, carry
out underpressure distillation after the removal of solvent under reduced pressure, collect 155-157 ℃/533Pa cut, promptly
2,5-dimethoxy-phenylethylamine (12.2g), yield 67.4%.1H?NMR(CDCl
3，500MHz)δ：2.81(2H，t)，2.95(2H，m)，3.71-3.74(6H，s)，6.48-6.61(3H，m)。m/z：182.190(M+H)+。 "
If the available hydrazine is 40%, can it be used instead of hydrazine-80% by multiplying by 2 (x2) the amount added to the mixture or is there a risk
of generating an unwanted hydrate?
Note: OCR is poor with Chinese language
ThanksAntigua - 12-6-2021 at 08:00
You didn't really read the document, did you?
This is just a Wolff-Kischner reaction you showed us here, the real starting material is 2,5-dimethoxy-alpha-amino-acetophenone. And the answer to
your question is... no and yes. Wolff-Kischner reactions are performed with as little water as possible as the water removal is the driving force for
the reaction. Maybe you should read about Clemmensen reduction, it seems more convenient here if you don't have access to 80% hydrazine.zed - 13-6-2021 at 00:56
Maybe this procedure works. Dunno!
40% Hydrazine can be concentrated. Look it up.clearly_not_atara - 13-6-2021 at 03:29
Sounds like a mistranslation. The rxn product should be dimethoxyphenylethane...karlos³ - 13-6-2021 at 04:04
Sounds like a mistranslation. The rxn product should be dimethoxyphenylethane...
Or maybe the "a-amino" in front of the acetophenone was lost in translation?
Because it says phenethylamine twice, once in the headline and in the text.Cookie Monster - 13-6-2021 at 15:23
