Herbicidal, insecticidal and acaricidal compsns. - contain new and known fluoro-substd. benz:hydrazido halide cpds.

摘要

Herbicidal, insecticidal and acaricidal compsns. contg. fluoro-substd. benzhydrazidoyl halides (I) are new. R1 = H, hal, CN, NO2, alkyl, alkenyl, alkynyl, alkoxy, alkenyloxy, alkynyloxy, alkylthio, alkenylthio, alkynylthio, haloalkyl, haloalkoxy, haloalkylthio, alkylamino, dialkylamino or opt. substd. phenyl, phenoxy or phenylamino; R2 = opt. substd. phenyl; X = hal; n = 0-4; the cpds. 2,3,4,5,6-pentafluoro-N-phenyl-benzhydrazidoyl chloride and 4-fluoro-N-phenyl-benzhydrazidoyl chloride are excluded. Cpds. (I) are new when (i) n = 0, F is ortho, X = Cl and R2 = 2-Cl-5-CH3- Ph or 2,5-diCl-Ph; (ii) n = 0, F is ortho, X = Br and R2 = 2-Cl-Ph; (iii) n = 0; F is meta, X = Cl and R2 = 2-Cl-Ph, 2,4- or 2,5-diCl-Ph or 2-Cl-5-CH3-Ph; or (iv) n = 0, X = Cl and R2 = 2- or 4-Cl-Ph, 2,3-, 2,4-, 3,4- or 2,5-diCl-Ph, o- or p-tolyl or 2-Cl-5-CH3-Ph. USE/ADVANTAGE - As herbicides, the compsns. are esp. useful as weedkillers, partic. for pre- or post-emergence control of monocot and dicot weeds in crops, e.g. winter rape and wheat as well as maize. They are also effective as defoliants, e.g. for cotton, and as desiccants, e.g. on footpaths. Cpds. (I) are more active herbicides and have better plant tolerance than N-(alpha-chloro-3'-chlorobenzylidene)- phenylhydrazine known from BE772681.