NEW MATERIAL:A 4-substituted-2,6-diphenylpyrimidine derivative expressed by formula I (R1 is lower alkyl, halogen or low haloalkyl at the o- or m-position; R2 is H, halogen or lower haloalkyl; R3 is lower alkoxy, lower alkylthio or lower alkylamino).
EXAMPLE: 2-(4-Trifluoromethylphenyl)-4-methylthio-6-(2-chlorophenyl)pyrimidine.
USE: Useful as a herbicide having herbicidal effects on broad-leaved weeds, such as chickweed or cleavars, in farmland and gramineous weeds, such as barnyard millet, without phytotoxicity to main crops, such as wheat and barley.
PREPARATION: A ketene dithioacetal derivative expressed by formula II (R4 is lower alkyl) is reacted with a benzamidine derivative expressed by formula III at 20-150°C temperature to afford the compound expressed by formula I.
SATO JUNICHI
SANEMITSU MINORU
HAMADA TATSUHIRO
MITO NOBUAKI
YOSHIDA AKIRA
