NEW MATERIAL:The compound of formula I (R is lower alkyl, lower alkenyl or lower alkynyl; X is Cl or Br; Y is O or S).
EXAMPLE: 2-[4-Chloro-2-fluoro-5-(1-methylethoxy)phenyl]aminothioxomethyl-3,4,5, 6-tetrahydro(1H,2H)pyridazine.
USE: A herbicide having herbicidal activity against broad-leaved weeds such as Sesbania exaltata, Ipomea purpurea, etc. and gramineous weeds such as barnyard grass, etc. in plowed land or paddy field, and against paddy field weeds such as arrowhead. It has no phytotoxicity to crops such as corn, soybean, cotton, rice, etc. It is useful as an active component of herbicide for foliar treatment or soil treatment of paddy field, plowed land, orchard, etc.
PROCESS: The compound of formula I can be prepared by reacting the tetrahydropyridazinecarboxylic acid ester of formula II (R' is lower alkyl) in a solvent in the presence of a base.
HASHIMOTO SHIYUNICHI
YOSHIDA AKIRA
MATSUMOTO KEIJI
KAMOMOTO KATSUZOU
Next Patent: JPS5970673