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Preparation method of 2-hydroxy-3-nitropyridine

A technology of nitropyridine and hydroxypyridine, which is applied in the field of preparation of 2-hydroxy-3-nitropyridine, can solve the problems of environmental pollution and unfavorable environmental protection, and achieve the reduction of pollutants, less waste liquid and gas, and high purity Effect

Inactive Publication Date: 2014-03-26
常熟市联创化学有限公司
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In the process of traditional synthesis of 2-hydroxy-3-nitropyridine, a large amount of organic waste liquid will be produced, and the discharge of these waste liquids into the environment will pollute the environment and is not conducive to environmental protection

Method used

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Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0013] Provide a kind of preparation method of 2-hydroxyl-3-nitropyridine, comprising the steps of:

[0014] (1) Add dropwise nitric acid with a mass percentage of 67% to 2-hydroxypyridine dissolved in pyridine, place the reaction bottle containing the 2-hydroxypyridine solution in an ice bath, take out the reaction bottle after the addition, and set the reaction bottle at room temperature Down stirring reaction 30 minutes;

[0015] (2) After concentrating the pyridine in the reaction flask to half the volume, repeat the operation of step (1) for 3 times, then add sodium bicarbonate to the obtained mixed solution until neutral, and add the alkali in the process of adding The reaction flask was placed in an ice bath, and post-treated to obtain 2-hydroxy-3-nitropyridine.

Embodiment 2

[0017] Provide a kind of preparation method of 2-hydroxyl-3-nitropyridine, comprising the steps of:

[0018] (1) Add dropwise nitric acid with a mass percentage of 60% to 2-hydroxypyridine dissolved in pyridine, place the reaction bottle containing the 2-hydroxypyridine solution in an ice bath, take out the reaction bottle after the addition, and set the reaction bottle at room temperature Down stirring reaction 30 minutes;

[0019] (2) After concentrating the pyridine in the reaction flask to half the volume, repeat the operation of step (1) for 4 times, then add sodium carbonate to the obtained mixed solution until neutral, and add the base as described in the process of The reaction flask was placed in an ice bath, and post-treated to obtain 2-hydroxy-3-nitropyridine.

Embodiment 3

[0021] Provide a kind of preparation method of 2-hydroxyl-3-nitropyridine, comprising the steps of:

[0022] (1) Add dropwise nitric acid with a mass percentage of 75% to 2-hydroxypyridine dissolved in pyridine, place the reaction bottle filled with the 2-hydroxypyridine solution in an ice bath, take out the reaction bottle after the dropwise addition, and set the reaction bottle at room temperature Down stirring reaction 25 minutes;

[0023] (2) After concentrating the pyridine in the reaction flask to half the volume, repeat the operation of step (1) for 5 times, then add sodium hydroxide to the obtained mixed solution until it is neutral, and add the alkali in the process of adding The reaction flask was placed in an ice bath, and post-treated to obtain 2-hydroxy-3-nitropyridine.

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PUM

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Abstract

The invention discloses a preparation method of 2-hydroxy-3-nitropyridine. The method comprises the following steps: dropwise adding nitric acid into 2-hydroxypyridine dissolved in pyridine, placing a reaction bottle containing the 2-hydroxypyridine solution in an ice bath, taking out the reaction bottle after the addition, and reacting for 20-40 min while stirring at room temperature; and concentrating the pyridine in the reaction bottle to half of the original volume, repeating the operations in the step (1) for 3-5 times, then adding alkaline into the obtained mixed solution in to a neutral state, and conducting posttreatment to obtain 2-hydroxy-3-nitropyridine. Through the above way, the 2-hydroxy-3-nitropyridine obtained by the preparation method of 2-hydroxy-3-nitropyridine provided by the invention has high purity and can be directly applied to the subsequent production without other treatment process. The method produces little waste liquid and waste gas in the preparation process, greatly reduces the pollutants discharged into the environment, and is conducive to the green production and suitable for large-scale promotion and application.

Description

technical field [0001] The invention relates to the field of fine organic synthesis, in particular to a preparation method of 2-hydroxy-3-nitropyridine. Background technique [0002] 2-Hydroxy-3-nitropyridine has the molecular formula C 5 h 4 N 2 o 3 , molecular weight 140.09686, melting point 212°C, yellow needle crystal, insoluble in benzene, ether, petroleum ether and cold water, soluble in hot water and hot alcohol, easily soluble in dilute alkali, harmful to eyes, respiratory system and skin Stimulation, a few reports have carcinogenic consequences. 2-Hydroxy-3-nitropyridine is widely used in the fields of medicine, pesticide and organic synthesis, and can be used to synthesize 2-acetyl-3-aminopyridine, 2-bromo-3-aminopyridine, 3-amino-2 -Bromopyridine monohydrochloride and 2-bromo-3-nitropyridine. The traditional process of synthesizing 2-hydroxy-3-nitropyridine will produce a large amount of organic waste liquid, which will pollute the environment when discharge...

Claims

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Application Information

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IPC IPC(8): C07D213/64
CPCC07D213/64
Inventor 陈雪平
Owner 常熟市联创化学有限公司