Optimization Of Synthetical Craftwork And Solid-phase Organic Synthesis Of 1,4-2H-benzoxazine-3(4H)-ones

Benzoxazine compounds are one kind of highly active protoporhyrinogen oxidase (protox) inhibitors. These compounds can effectively control both monocotyledon weeds and dicotyledon weeds at lower dosage. The action mechanism is similar to p-nitro-o-substituted diphenylethers. They can result weeds albinism and decolorization, which are very important albinism herbicide. These compounds exhibited higher activity than diphenylethers and they are one of the most hot fields in pesticidal chemistry.The applications of benzoxazine compounds in pesticide and the latest advances of synthesis of 1,4-2H-benzoxazine-3(4H)-ones were reviewed in this article. The paper also reviewed the advances of solid-phase organic synthesis (SPOS), solid support and linker, synthetical strategies and some analytic methods, such as FT-IR, MS, NMR and magic angle spinning NMR.On basis of herbicidal active fluoro-substituted 1,4-2H-benzoxazine-3(4H)-ones (B2055), we synthesized several biological active phthalimides including benzoxazine ring and have patented. In order to industrialize benzoxazine compounds, we explored one method to synthesize 6-amino-7-fluoro-1,4-2H-benzoxazine-3(4H)- one with cheaper materials, less steps, higher yield and purity.SPOS is an important method to high-throughput parallel synthesis or combinatorial synthesis compound libraries. How to use a transmission FTIR such as KBr pellet method to monitor and optimize the esterification and etherification on Wang resin was introduced, and the reaction kinetics according to the FTIR spectrum were discussed in the paper.We can carry through SPOS based on convenient and reliable analytical method. In order to get a compound library of benzoxazine-ones, we synthesized 7-fluoro-l,4-2H-benzoxazine-3(4H)-ones on Wang resin via esterification, etherification, reduction, cyclization and cleavage reaction and optimized the reaction conditions according to analyze the reaction kinetics based on the IR spectrum.Each intermediates and target compounds were systematically studied, and the structures of the compounds were confirmed by IR, ~1H NMR, LC/MS. The spectrum properties of typical compounds were also analyzed.