Selective herbicide 2-dibenzofuranyl-oxy-alkanoic acid derivs. - prepd. e.g. by reacting alkyl 2-halo-propionate with 2-hydroxy-dibenzofuran

摘要

New dibenzofuranyloxy-alkanoic acid derivs. are of formula (I) In the formula X, Y and Z is H, 1-6C alkyl, 1-6C alkoxy, halogen, NO2, 1-4C haloalkyl, or (1-4C alkoxy)--1-4C alkyl), R1 and R2 are each H or 1-4C alkyl, R3 is OH, 1-9C alkoxy (opt. mono- or polysubstd. by halogen, OH, CF3, or 1-4C alkoxy) 2-8C alkoxyalkoxy, 3-12C alkoxyalkoxyalkoxy, 1-4C alkylthio, 2-4C alkenoxy, cyclohexyloxy (opt. substd. by CH3), phenoxy (opt. substd. by 1-3 halogen atoms, methyl and/or methoxy gps), benzyloxy, amino, 1-4C alkylamino (opt. substd. by COOH), di(1-4C alkyl)amino, hydrazino, N', N'-di(1-4C alkyl)-hydrazino, anilino, pyridylamino or benzyl amino (in which the phenyl or pyridine ring may be substd. by 1-3 halogen atoms, NO2, OH, 1-2C alkoxy, 1-2C alkyl and/or CF3 gps), or the gp. -OM in which M is the cation of an organic or inorganic base, and n = 0,1, 2 or 3. (I) are herbicides particularly useful for combatting broadleaved weeds in a wide range of crops, including cereals, rice, maize and leguminous plants.