New pyrazolyl-methylthio-pyridine N-oxide derivatives, useful as herbicides and plant-growth regulators, e.g. for inducing desiccation or reducing lodging

摘要

2-pyrazolyl-methylthio-pyridine-N-oxide derivatives (I) and their salts are new. 2-pyrazolyl-methylthio-pyridine-N-oxide derivatives of formula (I) and their salts are new. n : 0-2; m : 0-4; R1> and R2>hydrogen, halo or 1-6C alkyl, optionally substituted by one or more of halo, nitro and/or cyano; R3>halo, nitro, cyano, amino, hydroxy, 1-6C alkyl (optionally substituted by one or more of halo, nitro, cyano, 3-6C cycloalkyl, 1-6C (halo)alkoxy, 1-6C alkylthio, alkylsulfinyl or alkylsulfonyl [these 5 groups optionally substituted by one or more of halo, nitro or cyano]), 3-6C cycloalkyl, 1-6C alkylthio, alkylsulfinyl or alkylsulfonyl (these 4 groups optionally substituted by halo), or 1-6C alkoxy (optionally substituted by halo, nitro, cyano, 3-6C cycloalkyl, 1-6C (halo)alkoxy or 1-6C alkylthio); R4>hydrogen, cyano, halo, 1-6C (halo) alkylthio, 1-6C (halo)alkylsulfinyl, 1-6C (halo)alkylsulfonyl, 1-6C alkoxy (optionally substituted by one or more of halo, 1-6C (halo)alkoxy or 1-6C alkylthio), 3-6C cycloalkyl (optionally substituted by one or more halo) or 1-6C alkyl (optionally substituted by one or more of halo, 1-6C (halo)alkoxy or 1-6C alkylthio); R5>hydrogen, 1-6C (halo)alkyl, 1-6C (halo)alkoxycarbonyl, benzyl (optionally substituted by one or more of halo, nitro, cyano, 1-6C alkyl, 3-6C cycloalkyl, 1-6C (halo)alkoxy or 1-6C alkylthio), 3-6C cycloalkyl, 2-6C alkenyl or alkynyl, or heterocyclyl (saturated or unsaturated preferably with 1-3 heteroatoms, N, O and S, preferably 3-7 membered alicyclic or 5-6 membered aromatic, optionally substituted by one or more of 1-6C (halo)alkyl, halo, cyano, 3-8C cycloalkyl, OC(R7>)3 or SC(R7>)3); R7>hydrogen, fluoro or chloro; R6>hydrogen, cyano, halo, 1-6C (halo)alkylthio, (halo)alkylsulfinyl or (halo)alkylsulfonyl, 3-6C cycloalkyl (optionally substituted by one or more halo) or 1-6C alkyl (optionally substituted by one or more of halo, 1-6C (halo)alkoxy or 1-6C alkylthio). An independent claim is included for several methods for preparing (I). [Image] ACTIVITY : Herbicide; Pre-emergence Herbicide; Post-emergence Herbicide; Plant Growth Regulant. The compound 2-(5-Difluoromethoxy-1-methyl-3-trifluoromethyl-1H-pyrazol-4-ylmethylsulfanyl)-pyridine 1-oxide (Ia), at 2 kg/hectare, gave good control of e.g. Sinapsis alba; Echinochloa crus-galli; Cyperus ina and Setaria media. MECHANISM OF ACTION : None given.