Method of preparing derivatives of 1,5-diaryl-3-trifluoromethyl-delta2-pyrazolines that are racemic and enantiomerically pure
申请人:——
公开号:US20040019222A1
公开(公告)日:2004-01-29
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.
1
制备具有一般式1的化合物的程序,其中包括外消旋混合物(±)-1,以及对映纯化合物(−)-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、甲磺酰基或氨基磺酰基原子,条件是R2或R4的取代基之一是甲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-酮与苯基肼反应,然后用氯磺酸处理,或者通过与氯磺酸反应,然后与氢氧化钠反应,最后与亚砜氯反应来获得具有一般式(±)-1的外消旋混合物。通过这两种方法得到的产物与碳酸铵或氨反应,或与亚硫酸钠和碘甲烷或硫酸甲酯反应。此外,通过与旋光活性麻黄碱反应,然后形成每个对映体的钠盐,与亚砜氯和碳酸铵或氨反应,或者与亚砜氯后跟随着亚硫酸钠和碘甲烷或硫酸甲酯来解决具有一般式(±)-1的外消旋混合物,以分别获得一般式(−)-1和(+)-1的对映纯化合物。