N-single-substituted Phenyl -2 - (4,6 - Dimethoxy-pyrimidin-2 - Yl Oxy) Benzylamine Synthesis And Herbicidal Activity

It is reported that benzylamine and analogues have various biological activity. We have found that pyrimidinylbenzylamine compounds have special structure and strong herbicidal activity. This thesis is related to study on the synthesis of N-mono-substituted phenyl-2-(4,6-dimethoxypyrimidinyl-2-yloxo) benzylamine compounds and establishment of compound library. The herbicidal activity in greenhouse against barnyard grass, amaranth were tested .The starting material salicylaldehyde reacted with various mono-substituted phenylamine to obtain schiff base, and then schiff base was reducted to N-mono-substituted phenyl-2-hydroxylbenzylamine. The new compounds were prepared via the nucleophilic substitution with DMSP. Every new compound was characterized by IR, ~1H NMR, MS and elementary analyses. In this study, we found the key step is synthesis of schiff base and the reaction is strong influenced by the o-substituted group.The results of herbicidal activity in greenhouse showed that many compounds exhibit high herbicidal activity in high dosage. These compounds usually contain bromine atom , ester and methyl groups in the aniline substructures. However, N-2-brom phenyl-2-(4,6-dimethoxypyrimidinyl-2-yloxo) benzylamine exhibites excellent herbicidal activity both in high and low dosage.