This comes from patent
Patent FR971429
. The
patent FR56321 was an addition to this one.
Exemple 1 Transformation of ketones to their corresponding amines
The present invention allow us to obtain amines by reduction of ketones in the presence of excess ammonia.
Starting with cyclohexanone we obtain cyclohexylamine in the following manner:
5 parts nickel sulphate is dissolved cold in 80 parts NH3 20%. Fifteen parts cyclohexanone are added, stirred and the dissolution is helped by adding 20 parts 95% ethanol. The addition of 10 part of Zn powder signals the start of the reaction. Two more 10 parts of Zn powder are added successively. After a few hours, the solution is centrifuged and by proper treatment, we recover 70-72% cyclohexylamine.
In the same manner we obtain isopropylamine from acetone, isobutylamine from methylethylketone, etc.
Exemple 2 Transformations of nitrocetones into their corresponding aminoalcools
Solution 1
Nickel sulphate 80 parts
Water 600 parts
Solution 2
Isonitrosoacetophenone 200 part
Regular NH3 2670 parts
KOH 35% 120 parts
Shake solution 1 then add in one shot, 600 parts Zinc powder. 15 to 30 minutes later, start adding solution 2 keeping the temperature below 60-70 celsius. The addition should take 2-3 hours. The solution is left stirring for a few more hours. The solution is centrifuged to separate the zinc precipitate. The precipitate is washed several times with 250 parts distilled water. The washes are added to the solution separated by centrifugation as above. Potassium carbonate is added in sufficient quantity to extract the base just formed. After washing the extracted base, it can be reacted with sulphuric acid in the usual conditions to yield the sulphate salt. The yield starting with 200 parts of nitroketones is around 90% of theoric following the reaction
C6H5COCNOH-CH2 + 6H+ = C6H5COHCNH2CH2
Exemple 4 Transformation of oximes into primary amines
It is quite normal that oximes give their corresponding amines since nitro containing molecules are regularly transformed into amines. This way we obtain B-phenylethylamine from the oxime of acetophenone. The oximes of phenylacetone and benzylacetone give respectively with yields of 85-88%, the phenylisopropylamine and benzylisopropylamine.
Example 6 Reduction of a nitrile function to its primary amine
Diverse nitriles are reduced to their corresponding amine by the zinc/nickel couple by the addition of 4 hydrogen atoms. This way, benzyl cyanide gives phenyl ethylamine
Summary
The present invention has for goals:
1. A reduction or hydrogenation of organic compounds in aqueous or hydroalcoolic solvent, thas consists essentially in doing the reaction with the metallic couple Zinc/Nickel
2. An execution mode for this invention, that consists in preparing the Zinc-Nickel couple using nickel sulphate at a maximum concentration of 5% of the hydrated salt and of metallic zinc, and to effectuate the reduction at temperatures under around 50 Celsius
3. Application range from transformation of ketones in amines, nitroketones in aminoalcools, of ethylenic derivatives into saturated compounds, oximes into primary amines, of carboxylated aldehyde or ketone into alcool, and of nitriles into primary amines.
I translated the important parts. If anybody feel that some parts may be missing in the above translation, its just that they dont give more details. Remember this patent was applied for in the 1940's so a lot must have been learned about this system since then.