| abstract |
NEW MATERIAL:A phenoxyalkynecarboxylic acid derivative expressed by formula I (R 1 is substituted or unsubstituted aryl; R 2 to R 4 are H or lower alkyl; R 5 is H, lower alkyl or lower alkoxy; X is halogen, lower alkyl, lower alkoxy, NO 2 or CN; (m) is 0 or 1; (n) is 0 or 1 or 2). n EXAMPLE: (2-Chloro-4-fluoro)phenoxy-2-butynoic acid-O-benzylamide. n USE: A herbicide having excellent herbicidal action with extremely small phytotoxicity to crops, especially gramineous crops. n PREPARATION: A compound expressed by formula II is reacted with a compound expressed by formula III in the presence of a suitable condensing agent such as dicyclohexylcarbodiimide in a suitable solvent such as methylene chloride, normally at -10 to +40°C temperature to afford the compound expressed by formula I. n COPYRIGHT: (C)1991,JPO&Japio |