| 摘要 |
NEW MATERIAL:A phenoxyphenoxycrotonic acid derivative of formula I. EXAMPLE:Ethyl gamma-methyl gamma-[4-(4'=trifluoro methyl phenoxy) phenoxy] crotonate. USE:Herbicids having safety for useful broadleaf crops, e.g. daikon, soybean, peanut, cotton, linen, etc. to kill the Gramineae weed, e.g. barnyard grass, etc. PROCESS:a phenoxyphenol of formula II is reacted with an almost equimolar amount of a crotonic acid derivative of formula III: (X is halogen atom) in the presenee of a base, e.g. caustic soda, etc., as a delydrohalogenating agent, in a reaction solvent, e.g. water, methanol, etc. at 0-150 deg.C to give the desired compound of formula I. |
