| 摘要 |
A process for the preparation of a compound of formula (I), R1 represents halogen, haloalkyl, haloalkoxy, R4S(O)n-, or -SF5; R2 represents hydrogen or halogen; R3 represents halogen; R4 represents alkyl or haloalkyl; and n represents 0, 1 or 2; which process comprises oxidising a compound of formula (II); wherein R1, R2 and W are as defined above, with trifluoroperacetic acid in the presence of a corrosion inhibiting. |
