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Preparation method of chemical intermediate 3-hydroxyphthalic anhydride

A technology of hydroxyphthalic anhydride and hydroxyphthalic acid, which is applied in the field of preparation of chemical intermediate 3-hydroxyphthalic anhydride, can solve the problems of complex operation, environmental pollution, low yield, etc. The effect of reaction yield, reduction of production cost, and low cost of raw materials

Pending Publication Date: 2022-06-03
CHANGZHOU UNIV
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

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Problems solved by technology

[0008] Aiming at the problems of complex operation, serious environmental pollution and low yield in the synthesis method for preparing 3-hydroxyphthalic anhydride in the prior art, the present invention proposes a method using cheap 1,5-dihydroxynaphthalene as raw material, Use sodium hypochlorite to oxidize under the combined action of a phase transfer catalyst and a copper catalyst to generate 3-hydroxyphthalic acid, and then dehydrate to generate 3-hydroxyphthalic anhydride

Method used

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  • Preparation method of chemical intermediate 3-hydroxyphthalic anhydride
  • Preparation method of chemical intermediate 3-hydroxyphthalic anhydride
  • Preparation method of chemical intermediate 3-hydroxyphthalic anhydride

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Experimental program
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Effect test

Embodiment 1

[0032] Into the reaction flask was added 1,5-dihydroxynaphthalene (8.0g, 50.0mmol), dichloroethane (80ml), tetrabutylammonium bromide (0.81g, 2.5mmol), cuprous iodide 0.95g, 5.0 mmol), drip 10% sodium hypochlorite aqueous solution (48mL, 64.0mmol), react at room temperature for 2 hours, separate the organic layer dichloroethane after the reaction, the aqueous layer is acidified with dilute sulfuric acid, adjust pH to 2 ± 0.5, separate out Precipitate, filter, wash with water, purify and dry to obtain off-white solid 3-hydroxyphthalic acid (7.6 g, content: 98.1%), yield 81.9%, 1 H NMR (400MHz, CDCl 3 )d 7.08 (m, 2H), 7.46 (dd, J=8.4, 7.7Hz, 1H).

[0033] 3-Hydroxyphthalic acid (7.6g, 41.0mmol), cyclohexane (50mL), catalyst N,N-dimethylformamide (0.2mL) were added to the reaction flask, cooled to 5°C with an ice bath, Thionyl chloride (5.9 g, 50.0 mmol) was added dropwise, and the reaction was stirred at 10 ° C for 30 minutes, heated and heated, and reacted under reflux condit...

Embodiment 2

[0036] Into the reaction flask was added 1,5-dihydroxynaphthalene (8.0g, 50.0mmol), chloroform (120ml), tetrabutylammonium chloride (0.42g, 1.5mmol), cuprous chloride 1.0g, 10.0mmol ), drip 12% sodium hypochlorite aqueous solution (50mL, 80.0mmol), react at room temperature for 4 hours, separate the organic layer chloroform after the reaction, the aqueous layer is acidified with hydrochloric acid, adjust pH to 2 ± 0.5, separate out the precipitation, filter , washed with water, purified and dried to obtain off-white solid 3-hydroxyphthalic acid (7.0 g, content: 98.5%), yield 75.6%.

[0037] 3-Hydroxyphthalic acid (7.0 g, 37.9 mmol), n-hexane (60 mL), catalyst N,N-dimethylacetamide (0.4 mL) were added to the reaction flask, cooled to 0°C with an ice bath, dropwise Add thionyl chloride (5.0g, 42.0mmol), stir and react at 10°C for 15 minutes, heat up and react under reflux conditions for 4 hours, after the reaction is completed, the organic solvent n-hexane is recovered under red...

Embodiment 3

[0039]Add 1,5-dihydroxynaphthalene (8.0g, 50.0mmol), dichloromethane (100ml), benzyltriethylammonium chloride (1.14g, 5.0mmol), cuprous bromide 1.43g to the reaction flask, 10mmol), drip 10% sodium hypochlorite aqueous solution (60mL, 80.0mmol), react at room temperature for 3 hours, separate the organic layer methylene chloride after the reaction finishes, the aqueous layer is acidified with phosphoric acid, adjust pH to 2 ± 0.5, separate out the precipitation, Filter, wash with water, purify and dry to obtain off-white solid 3-hydroxyphthalic acid (7.8 g, content: 98.4%), yield 84.3%.

[0040] 3-hydroxyphthalic acid (7.8g, 42.2mmol), n-heptane (80mL), catalyst N,N-diethylformamide (0.3mL) were added to the reaction flask, cooled to 5°C with an ice bath, Phosphorus oxychloride (10.0g, 65.2mmol) was added dropwise, and the reaction was stirred at 5°C for 20 minutes, heated and heated, and reacted under reflux conditions for 1 hour. After the reaction was completed, the organic...

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Abstract

The invention discloses a preparation method of a chemical intermediate 3-hydroxyphthalic anhydride, and belongs to the field of fine chemical engineering. According to the method, 1, 5-dihydroxynaphthalene which is low in price is adopted as a raw material, sodium hypochlorite is subjected to an oxidation reaction under the combined action of a phase transfer catalyst and a copper catalyst to generate 3-hydroxyphthalic acid, and then the 3-hydroxyphthalic acid and chlorination reagents such as thionyl chloride are subjected to a dehydration reaction under the catalysis of organic alkali to generate 3-hydroxyphthalic anhydride. The 3-hydroxyphthalic anhydride prepared by the method is high in yield and good in purity, the use of high-risk reagents and national precursor control chemicals is avoided, the reaction process conditions are mild, the reaction post-treatment is relatively economical, simple, convenient and safe, and the process technology can be used for industrial production.

Description

technical field [0001] The invention belongs to the field of fine chemical preparation, in particular to a preparation method of a chemical intermediate 3-hydroxyphthalic anhydride. Background technique [0002] 3-Hydroxyphthalic anhydride has a wide range of uses and is an intermediate in fine chemicals such as medicines, pesticides, and photosensitive materials. This product can be used to develop modified human serum albumin, which has high bactericidal power, can prevent the sexual transmission of HIV, and can also produce a new coronavirus drug with strong transmission inhibition and low neutralizing antibody sensitivity. The intermediates and resins of high-efficiency paddy field herbicides have broad market application prospects. At present, there are many synthetic methods of 3-hydroxyphthalic anhydride publicly reported in domestic and foreign literatures, mainly including the following synthetic methods. [0003] Synthesis method one (see figure 1 ): Using 3-nit...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): C07D307/89B01J31/02B01J27/122
CPCC07D307/89B01J31/0239B01J27/122B01J35/19Y02P20/584
Inventor 徐德锋王海波胡航
Owner CHANGZHOU UNIV