| 摘要 |
The invention provides a process for the preparation of a compound of formula (I) in particular, wherein a compound of formula (II) is reacted with a dialkylsulphate. R1 is C1-C4haloalkyl; R2 is optionally substituted alkyl, optionally substituted aryl or optionally substituted heteroaryl; and R3 is methyl or ethyl. |
