44 results about "Meta-nitrobenzaldehyde" patented technology

The invention provides a phenanthroimidazole-fluorescein pH fluorescent probe containing two hydroxyl groups and a preparation method of the phenanthroimidazole-fluorescein pH fluorescent probe, relates to fluorescein pH fluorescent probes and preparation methods thereof and aims to solve the technical problems that the conventional fluorescein pH fluorescent probes have fewer modification sites and single structures and have no clear response sites and pH values cannot be detected quantitatively. The structural formula of the phenanthroimidazole-fluorescein pH fluorescent probe containing the two hydroxyl groups is shown in the specification. The preparation method comprises the following steps: 1, an intermediate compound I is prepared from phenanthrenequinone, m-nitrobenzaldehyde, aniline and ammonium acetate as raw materials and glacial acetic acid as a solvent; 2, an intermediate compound II is synthesized from the intermediate compound I, Raney nickel and a hydrazine hydrate solution; 3, an intermediate compound III is synthesized from fluorescein, a methanol solution, a sodium hydroxide solution and chloroform; 4, the pH fluorescent probe is synthesized from the intermediate compound II and the intermediate compound III as raw materials and an acid medium as a solvent. The pH fluorescent probe can be used for detecting and monitoring the pH values.

The invention provides a phenanthrimidazole micromolecule Fe3+ fluorescent probe and a synthesis method thereof and aims at solving the technical problems that an existing Fe3+ fluorescent probe is only applicable to acid and neutral identification environments and other metals interfere iron ion identification. The structural formula of the phenanthrimidazole micromolecule Fe3+ fluorescent probeis described in the specification. The synthesis method comprises the following steps: firstly, synthesizing an intermediate compound I with phenanthrenequinone, m-nitrobenzaldehyde and ammonium acetate; secondly, then synthesizing an intermediate compound II by utilizing the intermediate compound I, raney nickel and hydrazine hydrate solution; and thirdly, synthesizing the phenanthrimidazole micromolecule Fe3+ fluorescent probe with the intermediate compound II and 5-nitryl salicylaldehyde. The phenanthrimidazole micromolecule Fe3+ fluorescent probe can identify Fe3<+> in an aqueous phase system with the pH value of 3-12, is not interfered by other ions and can be used for detecting pollution of Fe<3+> in water.

The invention discloses a preparation method of zaleplon, and belongs to the technical field of medicinal chemistry. According to the method, m-nitrobenzaldehyde and triethylamine which are simple and cheap are adopted as raw materials, and a core skeleton of zaleplon is efficiently and highly selectively constructed through a one-pot cascade reaction without transition metal catalysis, so that the generation of isomers is avoided, the generation of byproducts is reduced, the yield of a target product is increased, and the synthesis cost is reduced; and simple nitro reduction modification is performed to prepare zaleplon. The whole route is short, reaction conditions are mild, operation is easy and convenient, and the method is suitable for industrial production.

The invention relates to a synthesis method of a cinildipine intermediate, namely methoxy ethyl 2-(3-nitrobenzylidene)acetacetate. The synthesis method comprises the steps of: (1) dropwise adding concentrated sulfuric acid to methoxy ethyl acetacetate under stirring, and then adding ethyl acetate; (2) adding m-nitrobenzaldehyde, reacting at room temperature, and after the reaction is stopped, standing overnight to separate out solids; (3) adding ethyl acetate until solids are completely dissolved, then washing with water and collecting an organic phase; and (4) evaporating to remove a solvent so as to separate out crystals, filtering and drying. As compared with the traditional preparation method of cinildipine condensation intermediate, the technical scheme provided by the invention has the advantages that: the obtained target product has high purity (more than 99%) and high yield ( more than 70%); and the synthesis method is mild in reaction conditions and simple and convenient to operate.

The invention provides a synthesis method of m-nitrobenzaldehyde. The method comprises the following steps: firstly, reacting, concretely carrying out reaction on copper nitrate, water, silver nitrate and benzaldehyde in a molar ratio of (1.03-1.1):(20-40):(0.001-0.0012):1.0, so that reaction mixture is obtained; secondly, preparing an m-nitrobenzaldehyde crude product, concretely, filtering while the reaction mixture is hot, so as to obtain mother liquor, and then cooling the mother liquor, filtering, and taking solid, so that the m-nitrobenzaldehyde crude product is obtained; and thirdly, preparing high-purity m-nitrobenzaldehyde, concretely, adding a water soluble solvent into the m-nitrobenzaldehyde crude product, filtering, and drying, so that high-purity m-nitrobenzaldehyde is obtained. By adopting the method provided by the invention, molar yield of the obtained m-nitrobenzaldehyde is more than 90%, chromatographic purity is more than 99.8%, and content of o-nitrobenzaldehyde is less than 0.1%; and fewer three wastes are produced in a production process, so that the method provided by the invention is environmentally friendly.

The invention provides a preparation method of a high-purity nitrendipine raw material medicine, which comprises the following steps: preparing a crude product 2-(3-nitrobenzylidene) ethyl acetoacetate at normal temperature by taking ethyl acetoacetate, 98% concentrated sulfuric acid and m-nitrobenzaldehyde as raw materials; then washing, centrifuging and drying to obtain a pure product 2-(3-nitrobenzylidene) ethyl acetoacetate; the preparation method comprises the following steps: adding ethyl 2-(3-nitrobenzylidene) acetoacetate into an organic solvent, then adding methyl 3-aminocrotonate and a moisture scavenger, carrying out heating reaction, after the reaction is finished, removing the moisture scavenger, cooling, stirring, centrifuging, and drying a solid to obtain nitrendipine. The purity of the nitrendipine bulk drug obtained by the preparation method of the high-purity nitrendipine bulk drug is 99.80% or above, and the impurity B and the impurity C are both less than 0.1%.

The invention discloses a preparation process of a hypotensive drug optically pure cilnidipine. The preparation process comprises the following steps: 1) in the presence of (S)-BINAP and a ferric ironcompound, adding ethyl cyano acetoacetate, m-nitrobenzaldehyde and 3-amino-2-methoxyethyl butenoate into isopropanol to react to obtain (R)-1,4-dihydro-2,6-dimethul-4-(3-nitryl phenyl)-3,5-dipicolinic acid-3-(2-cyano ethyl ester)-5-(2-methoxyl ethyl ester); 2) stirring the product in a tetrahydrofuran aqueous solution of alkali to react to obtain (R)-1,4-dihydro-2,6-dimethyl-4-(3-nitryl phenyl)-3,5-dipicolinic acid-5-(2-methoxyl ethyl ester); and 3) carrying out an esterification reaction with cinnamyl alcohol to obtain the optically pure (R)-cilnidipine. The three-step yield of the (R)-cilnidipine reaches up to 41%, ee% reaches up to 99.5%, and the preparation process is simple and suitable for industrial production.

he preparation method of the intermediate is characterized by comprising the following steps: with chiral hydroxy acid as a starting material, the chiral hydroxy acid reacts with isopropanol under the catalysis of lewis acid, then reacts with an acetoacetic acid reagent, and is directly cyclized with m-nitrobenzaldehyde and methyl 3-aminocrotonate in an alcohol solvent, then crystallization is performed in a low temperature environment for realizing chiral resolution, hydrolysis is performed by sodium hydroxide, and then acidization is performed by hydrochloric acid to obtain a product. the intermediate is characterized by being prepared by the following steps: with chiral hydroxy acid as a starting material,the chiral hydroxy acid reacts with isopropanol under the catalysis of lewis acid, then reacts with an acetoacetic acid reagent, and is directly cyclized with m-nitrobenzaldehyde and methyl 3-aminocrotonate in an alcohol solvent, crystallization and chiral resolution are realized in a low temperature environment, hydrolysis is performed by sodium hydroxide, and then acidization is performed by hydrochloric acid to obtain a product. The preparation method disclosed by the invention has the advantages that the preparation technology is simple, the resolution is easy, the product yield is high, the optical purity is good, the quality is stable, and the large-scale industrial production is easy.

The invention relates to the technical field of organic compound synthesis, in particular relates to an industrial production method of benzaldehyde, and aims to improve the product yield, reduce theproduction cost and reduce environmental damage. The preparation method is characterized by comprising the following steps: S1, adding copper nitrate, water, silver nitrate and catalyst potassium chlorate into a reaction device, heating, dropwise adding benzaldehyde, continuously heating, and carrying out heat preservation to react, so as to obtain a reaction mixed solution; and S2, filtering thereaction mixed solution to remove copper hydroxide precipitates to obtain a mother solution, cooling the mother solution, and filtering to obtain a solid m-nitrobenzaldehyde crude product with the content of o-nitrobenzaldehyde less than 0.5%; and S3, putting the m-nitrobenzaldehyde crude product into a reaction device, adding 3.0-3.5 volume times of a water-soluble solvent of the m-nitrobenzaldehyde crude product, heating, filtering to remove insoluble impurities, adding water of the same volume of that of the water-soluble solvent, filtering, taking out a precipitated solid, and drying to obtain the high-purity m-nitrobenzaldehyde.

The invention relates to the technical field of organic compound synthesis, in particular to a preparation method of benzaldehyde, and aims to improve the product yield, reduce the production cost andreduce environmental damage. The preparation method is characterized by comprising the following steps: S1, adding copper nitrate, water, silver nitrate and catalyst concentrated nitric acid into a reaction device, heating, dropwise adding benzaldehyde, continuously heating, and carrying out heat preservation to react, so as to obtain a reaction mixed solution; and S2, filtering the reaction mixed solution to remove copper hydroxide precipitates to obtain a mother solution, cooling the mother solution, and filtering to obtain a solid m-nitrobenzaldehyde crude product with the content of o-nitrobenzaldehyde less than 0.5%; and S3, putting the m-nitrobenzaldehyde crude product into a reaction device, adding 3.0-3.5 volume times of a water-soluble solvent of that of the m-nitrobenzaldehyde crude product, heating, filtering to remove insoluble impurities, adding water of the same volume of the water-soluble solvent, filtering, taking out precipitated solids, and drying to obtain the high-purity m-nitrobenzaldehyde.