2-(substituted phenyl)-6-hydroxy or alkoxy-5-substituted-4-pyrimidinecarboxylates and their use as herbicides

1. A compound of the formula I

wherein

Q represents a halogen, cyano, C 1 -C 4 alkyl, C 1 -C 4 haloalkyl, C 2 -C 4 alkenyl and epoxides thereof, C 2 -C 4 haloalkenyl and epoxides thereof, C 2 -C 4 alkynyl or C 2 -C 4 haloalkynyl;

R 1 represents H or C 1 -C 4 alkyl;

W represents H or halogen;

X represents halogen;

Y represents halogen, C 1 -C 4 alkyl, C 1 -C 4 alkoxy, C 1 -C 4 alkylthio, C 1 -C 4 haloalkyl, C 1 -C 4 haloalkoxy, C 1 -C 4 haloalkylthio, —NR 2 R 3 , C 1 -C 4 alkoxy-substituted C 1 -C 4 alkyl, C 1 -C 4 haloalkoxy-substituted C 1 -C 4 alkyl, C 2 -C 4 alkenyl, C 2 -C 4 haloalkenyl or C 1 -C 4 haloalkyl-substituted carbonyl;

Z represents halogen, C 1 -C 4 alkyl or C 1 -C 4 haloalkyl; and

R 2 and R 3 independently represent H or C 1 -C 4 alkyl;

and agriculturally acceptable derivatives of the carboxylic acid group.

2. A compound of claim 1 in which the agriculturally acceptable derivatives of the carboxylic acid group are agriculturally acceptable salts, esters and amides.

3. A compound of claim 1 in which Q represents Cl, Br C 2 -C 4 alkenyl; R 1 represents H; W represents H; X represents F; Y represents F or OCH 3 ; and Z represents Cl.

4. A herbicidal composition comprising a herbicidally effective amount of a compound according to claim 1 , in a mixture with an agriculturally acceptable adjuvant or carrier.

5. A method of controlling undesirable vegetation which comprises contacting the vegetation or the locus thereof with or applying to the soil to prevent the emergence of vegetation a herbicidal composition according to claim 4 .