| 摘要 |
The present invention provides a process for the preparation of a compound of formula (I); wherein X is halogen; Y is ZR<1>; Z is oxygen or sulphur; and R<1> is C 1-6 alkyl, C1-6 haloalkyl or C3-7 cloalkyl; the process comprising either: hydrogenating a compound of formula (II); with a suitable transition metal catalyst in a C1-6 aliphatic alcohol, an ether, an hydrocarbon as solvent; or, b) conducting a one-pot hydrogenation of a compound of formula (III): wherein R<2> is phenyl optionally substituted by chloro,C1-6 alkyl, C1-6 alkoxy or (C1-6 alkyl)2N; firstly at about 20<°>C to form a compound of formula (IV): and then at about 40<°>C; both steps (I) and (ii) being carried out in the presence of a suitable catalyst and in the presence of a suitable solvent. |
