| 摘要 |
PROBLEM TO BE SOLVED: To obtain the subject compounds in a high yield by oxidizing a halopyridine with hydrogen peroxide and acetic acid in the presence of a specified cyclohexenedicarboxylic acid as a catalyst. SOLUTION: The composition of formula IV (R1 is H, a halogen, an alkyl, COOR2, CONR3R4 or the like; R2 is H or an alkyl; R3 and R4 are H or an alkyl; X is a halogen) is obtained by oxidizing (A) a halopyridine of formula I (R1 is H, a halogen, an alkyl or the like; X is a halogen) (e.g. 2-chloropyridine or the like) and (B) hydrogen peroxide in the presence of (C) acetic acid and (D) cyclohexenedicarboxylic acids of formula II or formula III (R5 is H or a 1-6C alkyl) (e.g. 1-cyclohexene-1,2-dicarboxylic acid, 1-cyclohexene-1,2- dicarboxylic acid anhydride or the like). In the above mentioned reaction, it is preferable to use 0.5-5 mol ingredient a, 0.5-2 mol ingredient C and 0.05-0.8 mol ingredient D per 1 mol ingredient A. |
