Patent ID: 6124469
Filing Date: 2000-09-26
Classification: C07D

Abstract:
A process for preparing sulfur-containing 2-chloro-3-(4,5-dihydro-3-isoxazolyl)benzoic acids of the formula Ia or Ib ##STR7## where the substituents have the following meanings: m is 0 or 1;R.sup.1 C.sub.1 -C.sub.6 -alkyl, C.sub.1 -C.sub.6 -haloalkyl;R.sup.2,R.sup.3,R.sup.4 hydrogen, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -haloalkyl orR.sup.3 and R.sup.4 together form a C.sub.2 -C.sub.6 -alkanediyl chain which may be substituted once to four times by C.sub.1 -C.sub.4 -alkyl,which comprisesa) brominating a thioether of the formula IV ##STR8## where R.sup.1 to R.sup.4 have the abovementioned meanings, with a brominating agent to give the bromo thioether of the formula V ##STR9## where R.sup.1 to R.sup.4 have the abovementioned meanings, and reacting the bromo thioether Vb) with magnesium powder and/or a Grignard compound of the formula VIR.sup.5 Mg--Hal VI,where Hal is Cl, Br or I and R.sup.5 is C.sub.1 -C.sub.6 -alkyl, in the presence of carbon dioxide to give alkylthiobenzoic acids of the formula Ia ##STR10## where R.sup.1 to R.sup.4 have the abovementioned meanings, and to prepare compounds Ib then, optionallyc) oxidizing with an oxidizing agent to the corresponding alkylsulfonyl and alkylsulfinylbenzoic acids of the formula Ib ##STR11## where R.sup.1 to R.sup.4 have the abovementioned meanings, and m can be 0 or 1.