Synthesis and Herbicidal Evaluation of 3-N-Substituted Amino-6-benzyloxypyridazine Derivatives

A variety of 3-N-substituted amino-6-benzyloxypyridazine derivatives were designed and synthesized in satisfactory yields. Their structures were confirmed by IR, 1H-NMR, and elemental analysis; compound 5j was further determined by X-ray diffraction crystallography. Their herbicidal activities were evaluated through barnyard grass and rape cup tests in laboratory bioassays. Most of the title compounds 5 displayed moderate herbicidal activities against the dicotyledonous plant Brassica campestris L. The most active compounds in the laboratory were also evaluated in the greenhouse.