| 摘要 |
1298642 Halopyrazoles UPJOHN CO 19 April 1971 [19 Feb 1970] 20465/71 Heading C2C Compounds of formula wherein each X is halogen, m is 2 or 3, n is 0 to 3, R is hydrogen, C 1-10 alkyl or C 1-10 alkenyl, the group RCHC n H 2n not containing more than 11 carbon atoms, and A is the carboxyl group, or a salt or C 1-8 alkyl ester thereof, the hydroxymethyl group or a C 1-9 alkanoyl ester thereof, the cyano group, or a carboxylic acid amide group, optionally substituted by listed groups, are prepared by one or more of (a) reaction of a halopyrazole salt with a haloester or halonitrile, (b) reduction of an ester to an alcohol, 4-dehalogenation occurring simultaneously, (c) ester hydrolysis, (d) reaction of an ester or acid halide with an amine, (e) dehydration of an amide to a nitrile with phosphorus pentoxide or phosphorus oxychloride, or (f) salification or salt hydrolysis. The products are herbicides and plant growth regulants. |
