Highly-potent herbicide R-acetochlor and preparation method therefor

Abstract

The invention discloses a highly-potent herbicide R-acetochlor and a preparation method therefor. The preparation method comprises the following steps: S1: dissolving Rac-acetochlor in ethanol so as to prepare a stock solution, then, carrying out chiral resolution on the stock solution by high-performance liquid chromatography, and carrying out separation, so as to obtain two types of enantiomers; S2: subjecting the prepared two types of enantiomers to electronic circular dichroism testing and vibrating circular dichroism testing separately, so as to obtain respective characteristic spectrograms of the two types of enantiomers; S3: carrying out conformation searching on standard structures of R-acetochlor and S-acetochlor, carrying out geometric optimization on obtained preferential conformations, calculating circular dichroism spectrograms of these preferential conformations, and superimposing the spectrograms of all the conformations according to Boltzmann distribution numbers of the spectrograms, so as to obtain calculated spectrograms of the R-acetochlor and S-acetochlor; and S4: comparing the characteristic spectrograms of the two types of enantiomers obtained in the step S2 with the calculated spectrograms obtained in the step S3, confirming the R-acetochlor. According to the preparation method, the time for separating acetochlor enantiomers is shortened, and highly-potent acetochlor can be extensively and rapidly prepared.

Description

technical field [0001] The invention belongs to the field of pesticides, and in particular relates to a high-efficiency herbicide R-acetochlor and a preparation method thereof. Background technique [0002] Herbicides are widely used in agriculture and account for the majority of agrochemicals used today. Enantiomers of chiral herbicides usually share the same physicochemical properties but often exhibit different biochemical effects. The "active body" may show a higher herbicidal effect, while other enantiomers may not, or even have the opposite effect. Using a single enantiomer for weed control can reduce the amount of herbicide used and reduce the total amount of chemical pollutants released into the environment. [0003] 2-Chloro-N-ethoxymethyl-6'-ethylacetyl-o-toluidine, known as acetochlor, is one of the most important herbicides in the world and one of the most used herbicides in China . It is used to control annual grass weeds and some small-seeded broadleaf weed...

AI Technical Summary

Problems solved by technology

However, there is still no literature to compare the resolution of acetochlor with commercially available chiral columns, to obtain the optimal resolution conditions, and there is no literature to reveal the preparation method of chiral acetochlor

In addition, the use of the empirical rules of the eight-region law has certain special requirements for the molecular structure, which cannot be promoted as a general method, and there is no more general method reported in the literature.

In addition, there is no report on acetochlor herbicidally high-efficiency bodies in the literature

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