Compounds of Fluorine - 3,5 Dichloro 6 or 2 - 3.5 - dibromo-4 piridiloxia cetico, 6 - fluor - 3.5 - Dichloro - methane - pyridyloxy or schedule 2 or 6 - fluor - 3Chlorine or Bromine - 2 - 5 piridiloxialqueno herbicides and compositions containing them

摘要

1472485 3,5 - Dihalo - 6 - fluoro - 2 - pyridyloxy compounds DOW CHEMICAL CO 10 April 1975 [11 April 1974] 14853/75 Heading C2C The invention comprises 3,5-dihalo-6-fluoro-2- pyridyloxy compounds of general formula wherein each X is the same and is Cl, Br or I; RSP1/SP is H or CH 3 ; and R is -CN; -COOH; -COORSP2/SP in which RSP2/SP is C 1-4 alkyl; -COOM where M is an ammonium ion, alkali metal, alkaline earth metal, Al or a transition group metal; -COCl; CH 2 OCORSP2/SP; -RSP3/SPOH in which RSP3/SP is C 1-4 alkylene; -CH= =CHOH; -CH=CHCH 2 OH; -CONRSP4/SPRSP4/SP where RSP4/SP is H or C 1-8 alkyl; -CONHCH 2 COOH; -CONRSP4/SPCH 2 CH 2 CH or -CH 2 OCONHHSP5/SP in which RSP5/SP is H or phenyl compounds where R is -COORSP2/SP are prepared by reaction of 6-fluoro-3,5-dihalo-2-pyridinol(II) with an - Br or Cl-acetic or propionic acid ester in the presence of Na or K and a lower alkanol. Compounds where R is -COOH are prepared by hydrolysis of the ester. When R is -COOM the products are obtained by reacting the free acid with an appropriate metal hydroxide or carbonate. Compounds where R is -CN are prepared by reaction of the pyridinol II Na or K salt with chloroacetonitrile. Where R is -COCl the compound is prepared by reacting the appropriate pyridyloxyacetic acid with SO 2 Cl 2 . Compounds with R representing -CH 2 OHSP2/SP, -CH 2 OÏ. -CH 2 OCH 2 CH 2 ORSP2/SP or -CH 2 OCH 2 CH 2 OCH 2 CH 2 OH are obtained from the appropriate pyridine derivative and glycol in the presence of NaH. When R is -CH 2 OCORSP2/SP or -CH 2 OCOC(Cl) 2 CH 2 the products are obtained from 2-(3,5-dihalo-6-fluoro- 2-pyridyl-oxyethanol and the acid chloride. Compounds in which R is -RSP2/SPOH, -CH= CHOH, -CH=CHCH 2 OH, -CH(OH)CH 2 OH or -CH 2 OCH 2 CH 2 OH are produced by reacting the pyridine derivative with a diol in the presence of an alkali metal hydroxide. When R is -CONRSP4/SPRSP4/SP the product is obtained by direct amination of the alkyl ester with NH 3 or an amine. Compounds with R=-CONHCH 2 COOH are prepared from the acid chloride and the appropriate 3,5 - dihalo - 6 - fluoro - pyridyloxyacetic acid with glycine Na or K salt. When R is -CONRSP4/SPCH 2 CH 2 OH the compound is obtained by reaction of the acid chloride with an amino ethanol. Amongst numerous Examples the compounds 3,5 - dichloro - 6 - fluoro - 2 - pyridyloxyacetic acid ethyl ester, 3-(3,5-dichloro-6- fluoro - 2 - pyridyloxy) - 1,2 - propanediol and N - [(3,5 - dichloro - 6 - fluoro - 2 - pyridyloxy)- acetyl] glycine are prepared. Herbicidal compositions comprise as active agent a compound of formula I in admixture with an inert carrier.