Novos compostos herbicidamente, acaricidamente e inseticidamente ativos

PCT No. PCT/EP92/00452 Sec. 371 Date Sep. 17, 1993 Sec. 102(e) Date Sep. 17, 1993 PCT Filed Mar. 2, 1992 PCT Pub. No. WO92/16510 PCT Pub. Date Oct. 1, 1992.The present invention relates to herbicidally, acaricidally and insecticidally active pyrazolidine-3,5-diones of the formula I (I) in which R1 is R2 and R3 independently of one another are C1-C6alkyl; C3-C6alkenyl; or C3-C6alkynyl; or R2 and R3 together are a -(CH2)3-, -(CH2)4-, -CH2-CH=CH-CH2-, -CH2-CH=CH- or -(CH2)2-CH=CH- bridge which is unsubstituted or up to trisubstituted by C1-C4alkyl; n is 0; 1; 2; 3; or 4; m is 0; or 1; the total of m and n being less than, or equal to, 4; the R4 radicals independently of one another are halogen; nitro; cyano, C1-C4alkyl; C1-C4haloalkyl; C1-C10alkoxy; C1-C4haloalkoxy; C3-C6alkenyloxy; C1-C4alkoxy-C2-4alkoxy; C3-C6alkynyloxy; C1-C4alkylcarbonyl; C1-C4alkoxycarbonyl; C1-C4alkylthio; C1-C4alkylsulfinyl; C1-C4alkylsulfonyl; amino; mono-C1-C4alkylamino; di-C1-C4alkylamino; R5 is X is oxygen; sulfur; CH2; or NR7; o is 0; 1; 2; or 3; R6 radicals independently of one another are C1-C4alkyl; halogen; C1-C4haloalkyl; C1-C4haloalkoxy; C1-C4alkoxy; nitro; cyano; C1-C4alkoxycarbonyl; amino; mono-C1-C4alkylamino; or di-C1-C4alkylamino; and R7 is hydrogen; C1-C4alkyl; formyl; or C1-C4alkylcarbonyl; the acid addition salts thereof, as well as processes for their preparation, and novel intermediates for these processes. The invention furthermore relates to herbicidally, acaricidally or insecticidally active compositions as well as to methods for controlling weeds, Acarina or insects.