| 主权项 |
1. A process for obtaining a compound of formula I: wherein R1 is a hydrogen atom, F, Cl, I, Br, (C1-C4)-alkyl or —CN; R2 is a heteroaryl residue selected from the series consisting of pyrrole, furan, thiophene, imidazole, pyrazole, oxazole, isoxazole, thiazole, isothiazole, tetrazole, 1,2,3,5-oxathiadiazole-2-oxides, triazolones, oxadiazolone, isoxazolone, oxadiazolidinedione, triazole, 3-hydroxypyrrole-2,4-diones, 5-oxo-1,2,4-thiadiazoles, pyridine, pyrazine, pyrimidine, indole, isoindole, indazole, phthalazine, quinoline, isoquinoline, quinoxaline, quinazoline, cinnoline and β-carboline, wherein the heteroaryl residue is unsubstituted or is substituted once, twice or three times, independently of each other, by substituents selected from the series consisting of (C1-C5)-alkyl, (C1-C5)-alkoxy, halogen, nitro, amino, trifluoromethyl, hydroxy, hydroxy-(C1-C4)-alkyl-, methylenedioxy, ethylenedioxy, formyl, acetyl, cyano, hydroxycarbonyl-, aminocarbonyl- and (C1-C4)-alkoxycarbonyl-, or an aryl residue selected from the series consisting of phenyl, naphthyl, 1-naphthyl, 2-naphthyl, biphenylyl, 2-biphenylyl, 3-biphenylyl, 4-biphenylyl, anthryl and fluorenyl, wherein the aryl residue is unsubstituted or is substituted once, twice or three times, independently of each other, by substituents selected from the series consisting of (C1-C5)-alkyl, (C1-C5)-alkoxy, halogen, nitro, amino, trifluoromethyl, hydroxy, hydroxy-(C1-C4)-alkyl-, methylenedioxy, ethylenedioxy, formyl, acetyl, cyano, hydroxycarbonyl-, aminocarbonyl- and (C1-C4)-alkoxycarbonyl-; R3 is a hydrogen atom, or (C1-C4)-alkyl, or an aryl residue selected from the series consisting of phenyl, naphthyl, 1-naphthyl, 2-naphthyl, biphenylyl, 2-biphenylyl, 3-biphenylyl, 4-biphenylyl, anthryl and fluorenyl, wherein the aryl residue is unsubstituted or is substituted, independently of each other, once, twice or three times by substituents selected from the series consisting of —NO2, —O—(C1-C4)-alkyl, F, Cl and Br, or —O—C(CH3)3, or —O—CH(R7)-aryl, wherein the aryl residue is selected from the series consisting of phenyl, naphthyl, 1-naphthyl, 2-naphthyl, biphenylyl, 2-biphenylyl, 3-biphenylyl, 4-biphenylyl, anthryl and fluorenyl and is unsubstituted or is substituted, independently of each other, once, twice or three times by substituents selected from the series consisting of —NO2, —O—CH3, F, Cl and Br, and wherein R7 is a hydrogen atom or (C1-C4)-alkyl; said process comprising: a) mixing a compound of formula II: wherein R1, R2 and R3 are defined as in the compound of formula I, in an organic solvent or a mixture of organic solvents with an enantiomerically pure auxiliary; b) separating the salt composed of enantiomerically pure auxiliary and compound of formula I, by fractional crystallization; and c) isolating the compound of formula I from the salt composed of enantiomerically pure auxiliary and compound of formula I. |
