Procedure for the preparation of nitroxyl radicals of sterically hindered amines
AssigneeEnichem Synthesis S.p.A.
InventorsCarlo Neri, Silvestro Costanzi, Rosa M. Riva, Mariangela Angaroni
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Abstract
Procedure for the preparation of nitroxyl radicals of sterically hindered amines, consisting of the reaction of amines with hydrogen peroxide in the presence of a titanium containing catalyst, particularly in the presence of titanium silicalites. The catalyst can be recovered at the end of the reaction and recycled.
Claims21
A process for the preparation of a nitroxyl radical of a sterically hindered amine, comprising reacting a sterically hindered amine with hydrogen peroxide in the presence of a catalyst containing titanium selected from the group consisting of titanium silicalites and synthetic zeolites having the formula
- X.TiO.sub.2 (1-X)SiO.sub.2
- wherein X is a number between 0.0001 and 0.04, wherein said process is carried out either with or without a solvent.
A process for the preparation of a nitroxyl radical of a sterically hindered amine, comprising adding hydrogen peroxide, under continual stirring, to a mixture comprising a catalyst, secondary amine, and optionally a solvent, maintaining the mixture under stirring for a time ranging from 3 to 24 hours at a temperature of between 20.degree. and 100.degree. C., removing said catalyst by filtration, and recovering the product by extraction with an organic solvent.
Dependencies are inferred from the claim text.