Preparing optically active hydroxylamine comprises reacting an optically active amine with a hydrocarbon in a solvent and dissolving resulting aminonitrile in alcohol, oxidizing, cooling and drying the precipitate or oil

摘要

Preparing optically active hydroxylamine comprises: reacting an optically active amine with a hydrocarbon in a solvent; dissolving resulting aminonitrile in acetic acid mixture of alcohol; oxidation of this mixture by adding sodium tungstate dihydrate and hydrogen peroxide at 30-70[deg] C; cooling the reaction and removing the resulting precipitate or oil; optionally drying the precipitate; reacting obtained nitrone with a carboxylic acid; and reacting resulting optically active hydroxylamine salt with an aqueous alkaline solution and an organic solvent, separating and drying. Preparing optically active hydroxylamine and/or its salts comprises: (i) reacting an optically active amine of formula (I) or (Ia) with a hydrocarbon of formula (II) in a solvent comprising water, methanol, ethanol, benzene, toluene or xylene; (ii) dissolving resulting aminonitrile of formula (III) or (IIIa) from step (i) in alcohol I-acetic acid mixture; (iii) oxidizing the mixture obtained in step (ii) by adding sodium tungstate dihydrate and adding hydrogen peroxide at 30-70[deg] C; (iv) cooling the reaction at -30-30[deg] C and removing the resulting precipitate or oil after cooling; (v) optionally drying the precipitate obtained in step (iv) under inert gas or in vacuum; (vi) reacting nitrone of formula (IV) or (IVa) obtained in step (iv) or (v) with a carboxylic acid; and (vii) reacting optically active hydroxylamine salt obtained from step (vi) with an aqueous alkaline solution and an organic solvent, followed by separation and drying the resulting organic phase and suspending the dried organic phase in a apolar solvent and then filtering and drying the resulting optically active free hydroxylamine. Either R1, R2 : 1-8C alkyl, 3-8C cycloalkyl or 6-15C aryl (all optionally substituted); or R1R2 : 5-8C alkyl- or aryl cycle, where the alkyl, cycloalkyl or aryl is present in the side chain and/or contains heteroatoms and R1 and R2 are never same; R3 : phenyl or CN; and X : OH, Cl, Br or I. [Image].