Picolinic acid derivativee and herbicide

PURPOSE: To provide a new compound having excellent safety and useful as a herbicide, etc. CONSTITUTION: The compound of formula I [R is H, alkyl, alkenyl, alkynyl, etc.; R 1 and R 2 are alkyl, alkoxy, halogen, etc.; X is group of formula II (R 3 and R 4 are H, alkyl, alkoxy, alkynyl, etc.), etc.; Y is O, (cyano-substituted) methylene, carbonyl, etc.; Z is O, etc.; n is 0 or 1], e.g. 3-[(4,6- dimethoxypyrimidin-2-yl)oxy]-6-(N,N-dimethylamino)picolinic acid methyl ester. The compound of formula I can be produced e.g. by reacting a compound of formula III (R 10 is R except for H) with a compound of formula IV (R 11 is halogen, alkylsulfonyl, etc.) in a solvent (e.g. benzene) in the presence of a base (e.g. sodium hydroxide). COPYRIGHT: (C)1993,JPO&Japio