Preparation process of ethyl chromane-4-formate

A technology of ethyl formate and preparation process, applied in the field of preparation of organic compounds, can solve problems such as high cost and low yield, and achieve the effects of cost reduction and yield improvement

Inactive Publication Date: 2012-07-25
苏州莱克施德药业有限公司
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] At present, in the synthetic route of this compound, phenol and 3-chloropropionyl chloride are used as starting materials, but the expensive trifluoromethanesulfonic acid reagent is used as the catalyst of the Friedel-Crafts acylation reaction, which has high cost and low yield. shortcoming

Method used

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  • Preparation process of ethyl chromane-4-formate
  • Preparation process of ethyl chromane-4-formate
  • Preparation process of ethyl chromane-4-formate

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] The preparation technology of chroman-4-ethyl carboxylate is made up of following four steps:

[0026] Step 1: Friedel-Crafts acylation, cyclization

[0027] (1) Under a nitrogen environment, put 1.6kg of compound phenol of formula 1 into a 20L four-necked bottle equipped with a condenser and mechanical stirring, that is, 17.0mol, and 10L of dry nitrobenzene as a solvent, and heat to dissolve completely;

[0028] (2) reactant is cooled to room temperature subsequently, drop into 2.2kg of 3-chloropropionyl chlorides, i.e. 17.0mol;

[0029] (3) A total of 5 kg of anhydrous aluminum trichloride was added into the reactant within 1 hour in ten times, and the hydrogen chloride gas produced was absorbed by sodium hydroxide solution, and the reactant was stirred at 40-45°C for 5 minutes after stirring for 1 hour. Hour, track with HPLC, until reaction finishes;

[0030] (4) After the reactant was cooled to room temperature, add 25 kg of ice and 6 L of concentrated hydrochlori...

Embodiment 2

[0051] Embodiment 2 is basically the same as Embodiment 1, and the only difference is that step 1 is different, as follows:

[0052] Friedel-Crafts acylation, cyclization

[0053] (1) Under a nitrogen atmosphere, put 0.16kg of compound phenol of formula 1 into a 2L four-neck flask equipped with a condenser and mechanical stirring, that is, 1.7mol, add 1L of dry 1,2-dichloroethane as a solvent, and heat to dissolve completely ;

[0054] (2) The reactant is cooled to room temperature, and 0.22kg of 3-chloropropionyl chloride is dropped into, i.e. 1.7mol;

[0055] (3) 0.5 kg of anhydrous aluminum trichloride was added in 5 times within 1 hour, the hydrogen chloride gas generated was absorbed with sodium hydroxide solution, the reactants were stirred for 1 hour and then reacted at 40-45°C for 5 hours, followed by HPLC , until the end of the reaction.

[0056] (4) The reactant is cooled to room temperature, add 2.5kg ice and 0.6L concentrated hydrochloric acid, stir for 30 minut...

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Abstract

The invention relates to a preparation process of ethyl chromane-4-formate. The preparation process is characterized by comprising the following steps of: carrying out Friedel-Crafts acylation reaction and cyclization, addition reaction, hydrolysis reaction and esterification reaction, wherein, in the Friedel-Crafts acylation reaction and cyclization, the Friedel-Crafts acylation reaction is carried out in the presence of anhydrous aluminium trichloride by using a compound of formula 1 and 3-chloropropionylchloride as initial raw materials, then carrying out cyclization on an obtained product and 10% NaOH to obtain a compound of formula 2; in the addition reaction, the addition reaction is carried out on the compound of formula 2 and trimethylsilyl cyanide in the presence of zinc iodide to obtain a compound of formula 3; in the hydrolysis reaction, the compound of formula 3 is hydrolyzed under the conditions of stannous chloride dihydrate, concentrated hydrochloric acid and acetic acid to obtain a compound of formula 4; and in the esterification reaction, the compound of formula 4 is esterified in the presence of concentrated sulfuric acid to obtain a compound of formula 5. According to the preparation process, expensive trifluoromethanesulfonic acid is replaced with cheap anhydrous aluminium trichloride in the Friedel-Crafts acylation step, and the yield is improved, so that the cost of preparing the compound is greatly reduced, and the high-quality product is obtained; and compared with the traditional method, the preparation process has obvious advantages.

Description

technical field [0001] The invention belongs to the field of medicinal chemistry, and in particular relates to a preparation method of an organic compound. Background technique [0002] Chroman-4-ethyl carboxylate is widely used as an intermediate in pharmaceutical chemicals and fine chemicals. Its structural formula is as follows: [0003] [0004] At present, in the synthetic route of this compound, phenol and 3-chloropropionyl chloride are used as starting materials, but the expensive trifluoromethanesulfonic acid reagent is used as the catalyst of the Friedel-Crafts acylation reaction, which has high cost and low yield. shortcoming. Contents of the invention [0005] The invention overcomes the disadvantages of the prior art and provides a process for preparing chroman-4-ethyl carboxylate with low cost, high yield and high product quality. [0006] In order to achieve the above object, the technical scheme adopted in the present invention is: a kind of preparation...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): C07D311/04
Inventor 孙光明顾志锋庄江俞菊荣
Owner 苏州莱克施德药业有限公司
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