Process for the preparation of Thioethers

摘要

3-(2-Alkylthio-5-acylphenyl)-isoxazoles (I) are prepared by a multi-stage process via 3-(2-aminophenyl)-isoxazole intermediates (VI). Also new are various oxime and isoxazole derivative intermediates, including (VI); and methods for preparing oximes (XV) and thioethers (XIX) . Preparation of 3-(2-alkylthio-5-acylphenyl)-isoxazoles of formula (I) involves preparing a 3-(2-aminophenyl)-isoxazole intermediate of formula (VI), then halogenating, thioalkylating, oxidizing and acylating to give (I). [Image] R 1, R 3-R 5 : H or 1-6C alkyl; or R 4+R 5 : a bond; R 2 : 1-6C alkyl; R 6 : heterocycle; n : 0-2. Independent claims are included for: (i) new oxime and isoxazole derivative intermediates of formulae (III), (X) (including (VI)) and (XII); (ii) the preparation of benzaldoxime derivatives of formula (XV), involving the reaction of toluene derivatives of formula (XVI) with an organic nitrite of formula R-ONO in presence of a base, where the process optionally further includes the conversion of the oxime group of (XV) into aldehyde, nitrile or nitrile oxide; (iii) the preparation of thioethers of formula (XIX), involving the reaction of an aniline of formula (XX) with a dialkylsulfide of formula R 2SSR 2 (VII) in presence of a catalyst; and (iv) new benzaldoxime compounds of formula (XV'). [Image] [Image] A : NO 2, NH 2 or SR 2; X : NO 2 or SO 2R y; R x, R y : inert substituents; m : 0-4; p : 0-5; R' 1 : H, 1-6C alkyl, halo, 1-6C alkoxy or 1-6C alkylthio; X' : S(O) nR' y; R' y : H, Cl or Br '' in the para position of the phenyl ring to X' '' (sic). ACTIVITY : Herbicidal. MECHANISM OF ACTION : None given.