| abstract |
THE INVENTION PROVIDES A PROCESS FOR PREPARING A COMPOUND OF THE FORMULA :-(FORMULA I)OR A BASE SALT THEREOF, WHEREIN R2 IS HYDROGEN OR C1-C6 ALKYL OPTIONALLY SUBSTITUTED BY UP TO 3 SUBSTITUENTS EACH INDEPENDENTLY SELECTED FROM C1-C6 ALKOXY AND C1-C6 ALKOXY (C1-C6 ALKOXY)-; AND R3 IS C1-C6 ALKYL OR BENZYL, SAID BENZYL GROUP BEING OPTIONALLY RING-SUBSTITUTED BY UP TO 2 NITRO OR C1-C4 ALKOXY SUBSTITUENTS, COMPRISING REACTION OF A COMPOUND OF THE FORMULA : -(FORMULA II) WHEREIN R1 IS C1-C4 ALKYL, PHENYL, BENZYL OR C1-C4 ALKOXY; AND R2 AND R3 ARE AS PREVIOUSLY DEFINED FOR A COMPOUND OF THE FORMULA (I), WITH HYDROGEN PEROXIDE OR SOURCE OF PEROXIDE IONS: SAID PROCESS BEING OPTIONALLY FOLLOWED BY CONVERSION OF THE COMPOUND OF THE FORMULA (I) TO A BASE SALT THEREOF. |