| 摘要 |
<p>1435639 Pyrazolium compounds AMERICAN CYANAMID CO 15 Aug 1974 [21 Sept 1973 (3)] 36036/74 Heading C2C The invention comprises the compounds of the formula wherein R 1 and R 2 are each C 1 -C 4 alkyl, R 3 is cycloalkylmethyl, cycloalkyl, methyl-substituted cycloalkyl, cycloalkenyl, methyl-substituted cyclalkenyl, (C 2 -C 11 ) alkyl or R 4 is cycloalkylmethyl, cycloalkyl, methylsubstituted cycloalkyl, cycloalkenyl, methylsubstituted cycloalkenyl, (C 2 -C 11 ) alkyl or in which the cycloalkyl and cycloalkenyl groups of R 3 and R 4 have 3-7 carbon atoms; Y, Y<SP>1</SP>, Z and Z<SP>1</SP> are each H, halogen, NO 2 , CH 3 S, CH 3 SO 2 , CN, COOH, carbo (C 1 -C 4 ) alkoxy, (C 1 -C 4 ) alkyl, (C 1 -C 4 ) haloalkyl containing 1 to 4 halogen atoms or (C 1 -C 4 ) alkoxy; X is anion with a charge of from 1 to 3; n is 0 or 1 and m is 1, 2 or 3. They may be obtained by reacting a diketone of the formula with a hydrazine of the formula RNHNH 2 to form a pyrazole which is then alkylated to give the required pyrazolium salt; wherein R is H or C 1 -C 4 alkyl. Herbicidal compositions comprise the above compounds of Formula I in association with conventional carriers or diluents and optionally surfactants. They have selective control and are useful both as pre-emergence and postemergence herbicides. The diketones of Formula II above may be obtained by reacting a methyl ketone of the formula R 3 COCH 3 with an alkyl carboxylic acid ester of the formula</p> |
