A method for synthesizing naphthoquinone compounds by utilizing photocatalytic oxidation of naphthol compounds

Abstract

The invention discloses a method for synthesizing naphthoquinone compounds by photocatalytic oxidation of naphthol compounds, comprising the steps of dissolving the naphthol compounds in a mixed solution of isopropanol and water to obtain a reaction liquid, transferring the reaction liquid to a photochemical reactor, introducing oxygen continuously into the photochemical reactor, irradiating the reaction liquid with LED monochromatic light having a wavelength of 450 nm, and continuously stirring for reacting to obtain the products, naphthoquinone compounds. The monochromatic LED light having the wavelength of 450 nm are used to replace high-pressure mercury lamp light in common photo-oxidation process, and by utilizing the monochromatic LED light used herein and the products naphthoquinone compounds having superposition of their absorption spectra, spontaneous photo-oxidation process and the yield of 90% and above can be achieved without adding a photosensitive agent, reaction cost is greatly saved, side reactions are reduced, and the products are easy to separate and purify and have high commercial value.

Description

technical field [0001] The invention relates to the technical field of photocatalytic oxidation synthesis. More specifically, it relates to a method for synthesizing naphthoquinone compounds by photocatalytic oxidation of naphthol compounds. Background technique [0002] Juglone naturally exists in Juglandaceae plants, mainly extracted from black walnut fruit and Juglans juglans green pericarp. Common pathogenic bacteria and spoilage bacteria, herbicides, insecticides and other biological activities, but also the precursor of many drugs, has a wide range of application value in the fields of medicine, food, daily necessities and so on. [0003] In addition, studies have shown that juglone also exhibits physiological toxicity to organisms. The literature [Westfall B.A., Russell R.L., Auyong T.K.Depressant agent from walnut hulls[J]. Science, 1961,134:1617] reported that juglone was administered to mice The LD50 of medicine is 2.5mg / kg, and the LD50 of intraperitoneal inject...

AI Technical Summary

Problems solved by technology

However, there are many deficiencies in this method: first, Juglans catalpa is a national second-class protected plant and is an endangered tree species; secondly, the content of juglone in the bark, leaves and green peel of hickory is not high; Quinone has sublimation property, and storage stability is not good, along with the increase content of pecan plant (comprising bark, leaf and green fruit peel) storage time reduces; In addition, various extraction methods and techniques are not mature enough at present

But this method productive rate is only 40-50%, even prolonging reaction time, the raising of productive rate is also very limited

At the same time, it is also necessary to add a photosensitizer to the reaction to replace the oxidant, resulting in an additional sensitizer treatment step in the post-reaction treatment process.

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