| 摘要 |
Process for preparing 2-(2-(3-Aryl-1,2,4-thiadiazol-5-yloxy)phenyl)-3-fluoromethoxy-acrylate esters of formula (Ia) comprises a) reacting an aryl acetic acid ester derivative of formula (V) with a formic acid derivative of a dialkylformamide acetal or a bis-dialkylaminoalkoxymethane (optionally in the presence of a diluent and/or basic catalyst) at -20 to 120 degrees C, preferably -10 to 80 degrees C, and reacting the obtained enol of formula (VI) directly with fluorobromomethane or fluorochloromethane (optionally in the presence of a diluent and/or base) at -20 to 120 degrees C, preferably -10 to 80 degrees C, to give the fluoromethyl ether of formula (IV); b) hydrolysing (IV) (optionally in the presence of a diluent and/or acid) at -20 to 120 degrees C, to give the hydroxyaryl compound of formula (II); and c) reacting (II) with an aryl-thiadiazole compound of formula (III) (optionally in the presence of a diluent and/or an acid acceptor) to give (Ia). Ar = optionally substituted aryl; Q = optionally substituted alkoxy; and X = halo, alkylsulphonyl or arylsulphonyl. The individual steps are independently claimed. Compounds (I) of formula (Ia; Ar = substituted aryl) are new. (II), (IV) and (V) are new. |
