Synthesis and herbicidal activities of novel 3‐(substituted benzyloxy or phenoxy)‐6‐methyl‐4‐(3‐trifluoromethylphenyl)pyridazine derivatives

Abstract

The results showed that a substituted phenoxy group at the 3-position of the pyridazine ring and the electron-withdrawing group at the para-position on the benzene ring were essential for high herbicidal activity.

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

“…The herbicidal activities of the title products 5 were determined with B. campestris and E. crus‐galli as examples of annual dicotyledonous and monocotyledonous plants, respectively, using reported laboratory methods , and the results were listed in Table . In addition, the herbicidal activities were also bioassayed in the glasshouse on four species representative of monocotyledonous and dicotyledonous plants (Table ). Through these tests, we can comprehensively evaluate the herbicidal activities of the title compounds.…”

“…The herbicidal activities of the title compounds were evaluated using a previously reported procedure . For glasshouse tests, all the experiments were performed under natural light conditions at 18–28°C.…”

“…The new discoveries have led us to synthesize a series of 3‐substituted benzyloxypyridazine analogs C (Fig. ) , which showed excellent herbicidal activity against B. campestris . With the objective of advancing the earlier work, exploring the herbicidal activity of novel compounds, and studying the relationship of structure and herbicidal activity, 3‐ N ‐substituted amino‐6‐benzyloxypyridazine derivatives 5 were designed and synthesized.…”

“…In this article, the synthesis of the title compounds is described, as well as their herbicidal activities. The herbicidal activities of the title compounds were determined with B. campestris and E. crus‐galli as examples of annual dicotyledonous and monocotyledonous plants, respectively, using reported laboratory methods . In addition, some compounds were selected for bioassay in the glasshouse on four weeds representative of monocotyledonous and dicotyledonous plants .…”

Design, Synthesis, and Bioactivity Evaluation of Novel 3‐(Substituted Phenoxy)‐6‐Methyl‐4‐(3‐Trifluoromethylphenyl) Pyridazine Derivatives

“…The 3‐(substituted)phenoxylpyridazine derivatives including compound A (Fig. ) exhibited excellent bleaching herbicidal activities against the dicotyledonous plants B. camperstris and Amaranthus retroflexus in post‐emergence treatments with a dose of 75 g/ha (compound A: 90%, 99%, respectively), and their activity is better than that of the commercial bleaching herbicide diflufenican (44% at 75 g/ha) .…”