METHOD FOR PRODUCING AROMATIC FLUORINE COMPOUND AND FLUORINE-CONTAINING BENZENESULFINIC ACID DERIVATIVE TO BECOME ITS RAW MATERIAL

摘要

PURPOSE: To obtain the subject compound useful as an intermediate for agricultural chemicals and medicines in high yield without using a dangerous reagent and an expensive reagent by subjecting a specific aromatic sulfinic acid derivative to elimination reaction of sulfinic acid under a condition from acidity to basicity. ;CONSTITUTION: An aromatic sulfinic acid derivative of formula I (R is 1-4C alkyl, 1-4C alkoxy or H; X is alkali metal or H; Y is Cl or Br; (1) is 1-2; (m)is 0-3; (n) is 1-4; (1+m+n)=2-5) is subjected to elimination reaction of sulfinic acid under a condition of acidity to basicity to give the objective compound of formula II. In the case of the reaction under an acidic condition, an aqueous solution of sulfuric acid is preferably used as a solvent and under a basic condition, the reaction is preferably carried out in an aprotic solvent such as DMF by using sodium carbonate as a catalyst. 2,4-Difluoro-3-methylbenzenesulfinic acid and its alkali metal salt among the raw material compound of formula I are new compounds.;COPYRIGHT: (C)1993,JPO&Japio