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CN-121974880-A - Photosensitive herbicide and preparation method and application thereof

CN121974880ACN 121974880 ACN121974880 ACN 121974880ACN-121974880-A

Abstract

The invention relates to the technical field of herbicides, in particular to a photosensitive herbicide and a preparation method and application thereof, wherein the general structure of the photosensitive herbicide is A-L-B, wherein A is coumarin weeding active groups, B is growth inhibition regulating groups, and L is photosensitive connecting arms, and the photosensitive connecting arms comprise azo phenyl groups or o-nitrobenzyl groups and are cracked under irradiation of 365-450nm wavelength light. According to the invention, the photosensitive connecting arm is introduced between the weeding active group and the growth inhibition regulating group, so that the chemical agent is kept in a stable structure and a low-activity state after being sprayed at night, and the exposure risk and environmental load of non-target organisms are reduced from the source. Under the condition of natural illumination or illumination with specific wavelength, the photosensitive connecting arm is controllably cracked, the weeding active ingredients are accurately released, and the space-time matching between the release of the pesticide effect and the active period of photosynthesis of weeds is realized, so that the absorption efficiency and the action intensity of the pesticide are obviously improved.

Inventors

  • SUN JIALE

Assignees

  • 上海群力化工有限公司

Dates

Publication Date
20260505
Application Date
20260326

Claims (10)

  1. 1. The photosensitive herbicide is characterized by comprising a general structure of the photosensitive herbicide, wherein: A is coumarin weeding active group; b is a growth inhibition regulating group, which is an abscisic acid analogue or a salicylic acid derivative; L is a photosensitive connecting arm, wherein the photosensitive connecting arm comprises an azo phenyl group or an o-nitrobenzyl group, and the photosensitive connecting arm is cracked under the irradiation of 365-450nm wavelength light.
  2. 2. The photosensitive herbicide as claimed in claim 1, wherein, The coumarin herbicide active group comprises 7-hydroxy-4-methylcoumarin or halogenated derivatives thereof; The photosensitive connecting arm is respectively connected with the group A and the group B through ester bonds or amide bonds.
  3. 3. A process for preparing a photosensitive herbicide, which is suitable for preparing the photosensitive herbicide according to claim 1 or 2, comprising: Reacting a carboxyl-containing azo-phenyl group or an o-nitrobenzyl group with thionyl chloride to obtain a first intermediate; esterifying the coumarin weeding active group with the first intermediate to obtain a second intermediate; And (3) reacting the growth inhibition regulating group with the second intermediate in a condensing agent system, and purifying by column chromatography to obtain the photosensitive herbicide.
  4. 4. The method of claim 3, wherein the reacting the carboxyl group-containing azobenzene group or o-nitrobenzyl group with thionyl chloride provides a first intermediate comprising: mixing an azobenzene derivative or an o-nitrobenzyl derivative containing carboxyl with thionyl chloride according to a first preset molar ratio to obtain a first mixture; Adding N, N-dimethylformamide to the first mixture to obtain a second mixture; carrying out reflux reaction on the second mixture under a first preset condition to obtain a third mixture; The third mixture was purified by distillation under reduced pressure to obtain a first intermediate.
  5. 5. The preparation method of the glass fiber reinforced plastic composite material is characterized in that the first preset molar ratio is 1 (1.2-5.0), the first preset condition comprises that the reflux temperature is 60-80 ℃, and the reflux time is 2-6 h.
  6. 6. The method of claim 5, wherein the esterification reaction of the coumarin herbicide active group with the first intermediate to obtain a second intermediate comprises: dissolving the coumarin weeding active group in an organic solvent, and adding organic base and a catalyst to obtain a first substrate solution; Under a second preset condition, dripping the first intermediate into the first substrate solution to obtain a second substrate solution; Stirring the second substrate solution under a third preset condition to obtain a third substrate solution; And removing impurities from the third substrate solution to obtain a second intermediate.
  7. 7. The preparation method of claim 6, wherein the molar ratio of the first intermediate to the coumarin herbicide active group is 1 (1.0-1.5); the organic solvent comprises dichloromethane, tetrahydrofuran or acetonitrile; The organic base comprises triethylamine, pyridine or N, N-diisopropylethylamine; the catalyst comprises 4-dimethylaminopyridine; the second preset condition comprises that the temperature is 0-5 ℃ and the dripping time is 1-2 hours; the third preset condition comprises that the temperature is room temperature and the stirring time is 4-12 h.
  8. 8. The method of claim 7, wherein the step of reacting the growth-suppressing regulatory group with the second intermediate in a condensing agent system, and purifying by column chromatography to obtain the photosensitive herbicide comprises the steps of: mixing the second intermediate, a growth inhibition regulating group, an organic solvent, a condensing agent and an auxiliary catalyst to obtain a first reaction mixture; stirring the first reaction mixture under a fourth preset condition to obtain a second reaction mixture; removing impurities from the second reaction mixture to obtain a third reaction mixture; And (3) performing column chromatography purification on the third reaction mixture by using an eluent to obtain the photosensitive herbicide.
  9. 9. The method of claim 8, wherein the molar ratio of the second intermediate to the growth-suppressing modifier group is 1 (1.0-1.5); the organic solvent comprises dichloromethane, tetrahydrofuran or acetonitrile; The condensing agent comprises EDCI, DCC or HATU; the auxiliary catalyst comprises DMAP or triethylamine; The fourth preset condition comprises the steps of stirring at 0-5 ℃ for 0.5-2 hours, then heating to room temperature and stirring for 6-24 hours.
  10. 10. Use of the photosensitive herbicide according to claim 1 or 2, or the photosensitive herbicide prepared by the method for preparing a photosensitive herbicide according to any one of claims 3 to 9, for weed control.

Description

Photosensitive herbicide and preparation method and application thereof Technical Field The invention relates to the technical field of herbicides, in particular to a photosensitive herbicide and a preparation method and application thereof. Background Weed competition is one of the major factors affecting crop yield and stability of the agroecological system. The traditional herbicide is sprayed in daytime, which is favorable for the activity of the herbicide under sufficient illumination and quickens the action process, but the positive value of the period is a peak of the activity of various pollinating insects and beneficial arthropods, which is easy to cause the rise of exposure risk of non-target organisms, thereby influencing the biodiversity and ecological balance. In comparison, the night pesticide application can avoid pollinating insect activities to a certain extent, reduce ecological interference and have better environmental friendliness. However, environmental conditions such as insufficient illumination at night, lower temperature, heavier dew and the like often inhibit the biological activity of part of herbicides, physiological differences of crops and weeds in circadian rhythms also influence the absorption and transmission processes of the medicaments, miss the physiological time period during which photosynthesis of the weeds is most active, weaken the absorption and transmission efficiency of the medicaments in vivo, and lead to slow medicament effect and even reduced prevention and control effects. Therefore, how to ensure the weeding effect and simultaneously consider ecological safety becomes an important problem to be solved in the modern agriculture green management. Disclosure of Invention Object of the invention The invention aims to provide a photosensitive herbicide and a preparation method and application thereof, and the photosensitive herbicide is in a stable and low-activity state after being sprayed at night through a photosensitive connecting arm, and is subjected to directional cracking under the subsequent illumination condition and accurately releases active ingredients, so that the space-time matching of the drug effect release and the active period of photosynthesis of weeds is realized, the utilization efficiency of pesticides is obviously improved, and the influence on other organisms is reduced. (II) technical scheme In order to solve the problems, the invention provides a photosensitive herbicide, which comprises a general structure of the photosensitive herbicide, wherein: A is coumarin weeding active group; b is a growth inhibition regulating group, which is an abscisic acid analogue or a salicylic acid derivative; L is a photosensitive connecting arm, wherein the photosensitive connecting arm comprises an azo phenyl group or an o-nitrobenzyl group, and the photosensitive connecting arm is cracked under the irradiation of 365-450nm wavelength light. In another aspect of the invention, preferably, the coumarin herbicidally active group comprises 7-hydroxy-4-methylcoumarin or a halogenated derivative thereof; The photosensitive connecting arm is respectively connected with the group A and the group B through ester bonds or amide bonds. In another aspect of the present invention, preferably, a method for preparing a photosensitive herbicide, which is suitable for preparing a photosensitive herbicide as described above, comprises: Reacting a carboxyl-containing azo-phenyl group or an o-nitrobenzyl group with thionyl chloride to obtain a first intermediate; esterifying the coumarin weeding active group with the first intermediate to obtain a second intermediate; And (3) reacting the growth inhibition regulating group with the second intermediate in a condensing agent system, and purifying by column chromatography to obtain the photosensitive herbicide. In another aspect of the present invention, preferably, the reacting a carboxyl group-containing azo-phenyl group or an o-nitrobenzyl group with thionyl chloride to obtain a first intermediate, comprises: mixing an azobenzene derivative or an o-nitrobenzyl derivative containing carboxyl with thionyl chloride according to a first preset molar ratio to obtain a first mixture; Adding N, N-dimethylformamide to the first mixture to obtain a second mixture; carrying out reflux reaction on the second mixture under a first preset condition to obtain a third mixture; The third mixture was purified by distillation under reduced pressure to obtain a first intermediate. In another aspect of the invention, the first preset molar ratio is preferably 1 (1.2-5.0), the first preset condition comprises that the reflux temperature is 60-80 ℃, and the reflux time is 2-6 h. In another aspect of the present invention, preferably, the esterification reaction between the coumarin herbicide active group and the first intermediate is performed to obtain a second intermediate, which includes: dissolving the coumarin weeding active group in an