Procedure for the preparation of racemic and enantiomerically pure derivatives O F 1,5 diaryl-3-trifluorromethyl-delta2-pyrazolines
申请人:Alcon-Marrugat Montserrat
公开号:US20050096373A1
公开(公告)日:2005-05-05
Procedure for preparation of compounds with the general formula 1, which include the racemic mixtures (±)-1, and the enantiomerically pure compounds (−)-1 and (+)-1, wherein R
1
and R
3
, like or different, represent an atom of hydrogen, chlorine, fluorine, a methyl, trifluoromethyl or methoxy group; R
2
represents an atom of hydrogen, chlorine, fluorine, a methyl, trifluoromethyl, methoxy, trifluoromethoxy, methylsulphonyl or aminosulphonyl group; R
4
represents an atom of hydrogen, chlorine, fluorine, a methyl, trifluoromethyl, methoxy, trifluoromethoxy, methylsulphonyl or aminosulphonyl group, with the condition that one of the substituents R
2
or R
4
is a methylsulphonyl or aminosulphonyl group; which involves obtaining the racemic mixture with the general formula (±)-1 by reacting an (E)-1,1,1-trifluoro-4-aryl-3-buten-2-one with a phenylhydrazine, followed by a treatment with chlorosulphonic acid, or by reacting with chlorosulphonic acid followed by a reaction with sodium hydroxide and, finally, with thionyl chloride. The product obtained by either of these methods is made to react with ammonium carbonate or ammonia, or with sodium sulphite and methyl iodide or methyl sulphate. In addition, to obtain the enantiomerically pure compounds with the general formula 1 by resolving the racemic mixture with the general formula (±)-1, a reaction is effected with optically active ephedrine, followed by formation of the sodium salt of each enantiomer, reaction with thionyl chloride and ammonium carbonate or ammonia, or instead with thionyl chloride followed by sodium sulphite and methyl iodide or methyl sulphate to thereby obtain separately the enantiomerically pure compounds with the general formulae (−)-1 and (+)-1.
制备通式为1的化合物的程序,其中包括外消旋混合物(±)-1和对映纯化合物(-)-1和(+)-1,其中R1和R3,相同或不同,代表氢、氯、氟、甲基、三氟甲基或甲氧基原子;R2代表氢、氯、氟、甲基、三氟甲基、甲氧基、三氟甲氧基、甲基磺酰基或氨基磺酰基原子;R4代表氢、氯、氟、甲基、三氟甲基、甲氧基、三氟甲氧基、甲基磺酰基或氨基磺酰基原子,其中R2或R4的取代基之一为甲基磺酰基或氨基磺酰基;该程序包括通过将(E)-1,1,1-三氟-4-芳基-3-丁烯-2-酮与苯肼反应,然后用氯磺酸处理,或与氯磺酸反应,然后与氢氧化钠和亚磺酰氯反应,从而获得通式为(±)-1的外消旋混合物。通过这些方法得到的产物与碳酸铵或氨或亚硫酸钠和碘甲烷或甲磺酸甲酯反应。此外,通过用旋光性麻黄碱分离通式为(±)-1的外消旋混合物,随后形成每个对映体的钠盐,然后与亚磺酰氯和碳酸铵或氨反应,或者用亚磺酰氯后接着用亚硫酸钠和碘甲烷或甲磺酸甲酯,从而分别获得对映纯化合物(-)-1和(+)-1。