Preparation method of 1, 1-cyclopropane dimethanol

A technology of cyclopropanedimethanol and ethanol, applied in 1 field, can solve the problems of inability to meet the demand of intermediates, poor safety, complicated steps, etc., and achieve the effects of high safety, improved product quality, and simple process

Inactive Publication Date: 2012-10-31
ZHEJIANG HUTU PHARMCHEM
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The steps of this method are cumbersome. Either a relatively toxic solvent is used, or a less safe and more expensive reducing agent is used. ...

Method used

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Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0015] Add 500 g (11.1 mol) of ethanol and 250 g of dibromoneopentyl glycol (Yixing Zhongzheng, 99%, 0.954 mol) into a 1000 ml four-necked flask equipped with mechanical stirring, a thermometer, and a condenser tube, stir, and heat up to 60 degrees. Add 70g of 320-mesh zinc powder (Taizhou Zinc, 99%, 1.07mol) in 12 times, and finish the addition in about 2 hours. During the process, the reaction is exothermic, and cooling water is required to keep the reaction at about 60 degrees. After the addition, reflux for 1 hour , cooled to 10 degrees, 50g (99%, 2.94 mol) of ammonia was passed through, the reaction exothermic, the temperature was controlled at about 20 degrees, and the reaction was completed in about 1.5 hours, filtered, and the mother liquor was concentrated and rectified to obtain 1,1-cyclopropanedimethanol 89.4 g, 98% GC content, 92% yield; the above chemical reaction formula is:

[0016]

Embodiment 2

[0018] Put 900kg of ethanol and 500kg of dibromoneopentyl alcohol in a 2000L reactor, heat up and dissolve, add 135kg of zinc powder when it reaches 60 degrees, and finish adding in about 3 hours, reflux for 1 hour after adding, cool to 10 degrees, pass ammonia About 90kg, the temperature is controlled at about 20 degrees, passed through for 2 hours, filtered, the mother liquor is concentrated and rectified, and 180kg of 1,1-cyclopropanedimethanol product is obtained, the GC content is 98%, and the yield is 92.7%.

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Abstract

The invention relates to a preparation method of 1, 1-cyclopropane dimethanol. The method comprises the steps of conducting ring-closure reaction on organic dihalide and a reducing agent in an alcohol solvent under a certain condition to obtain a solution of 1, 1-cyclopropane dimethanol and halide salt, introducing ammonia under certain conditions so as to conduct solid-liquid separation, filter and rectify to obtain 1, 1-cyclopropane dimethanol. Due to the adoption of the preparation method, the process of 1, 1-cyclopropane dimethanol is simple and concise, the safety is high, and meanwhile, the yield reaches to more than 90%, the purity of 1, 1-cyclopropane dimethanol is more than 98%, and the quality of 1, 1-cyclopropane dimethanol is improved effectively.

Description

technical field [0001] The invention relates to a preparation method of 1,1-cyclopropanedimethanol. Background technique [0002] 1,1-Cyclopropanedimethanol is an important intermediate in the side chain synthesis of Montelukast sodium, and its synthesis method has attracted much attention. The more traditional method is to use diethyl malonate as a raw material to obtain 1,1-cyclopropanedimethanol through two steps of C-alkylation and reduction. In the C-alkylation reaction, polyethylene glycol (PEG )400 is used as a phase transfer catalyst to catalyze, and under the action of potassium carbonate, react with 1,2-dichloroethane to obtain 1,1-diethyl cyclopropanedicarboxylate; in the reduction reaction, reduce with potassium borohydride, in three Under the catalysis of aluminum chloride, 1,1-cyclopropanedicarboxylate is reduced to obtain 1,1-cyclopropanedimethanol, and the total yield of the two-step reaction is 50%-55%. The steps of this method are cumbersome. Eith...

Claims

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Application Information

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IPC IPC(8): C07C31/27C07C29/58C07C29/88
Inventor 余向阳
Owner ZHEJIANG HUTU PHARMCHEM
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