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, 1 H‐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.