阅读说明：本技术 一种氢硅烷还原制备1,2,4-丁三醇的方法 (Method for preparing 1,2, 4-butanetriol by reducing hydrosilane ) 是由 李学兵 陈灿 于培 姜军翔 李广慈 于 2020-08-11 设计创作，主要内容包括：本发明公开了一种氢硅烷还原制备1,2,4-丁三醇的方法,以聚甲基氢硅氧烷为还原剂,叔丁醇钾为催化剂,在二氧六环为溶剂的条件下将苹果酸二甲酯选择性地还原为1,2,4-丁三醇,还原剂价格低廉,反应条件温和,1,2,4-丁三醇选择性为100％,收率达到70％。(The invention discloses a method for preparing 1,2, 4-butanetriol by reducing hydrosilane, which takes polymethylhydrosiloxane as a reducing agent and potassium tert-butoxide as a catalyst, and selectively reduces dimethyl malate into 1,2, 4-butanetriol under the condition of taking dioxane as a solvent, wherein the reducing agent has low price and mild reaction conditions, the selectivity of 1,2, 4-butanetriol is 100 percent, and the yield reaches 70 percent.)

1. A method for preparing 1,2, 4-butanetriol by reducing hydrosilane is characterized by comprising the following steps: the method comprises the following steps:

(1) putting a certain mass of dimethyl malate, polymethylhydrosiloxane and a certain volume of 1, 4-dioxane into a single-mouth round-bottom flask, uniformly mixing, adding a certain mass of potassium tert-butoxide under stirring, and reacting for 48 hours in a constant-temperature oil bath.

(2) After the reaction in the step (1) is finished, slowly dripping a certain volume of methanol-potassium hydroxide solution into the reaction system to stop the reaction, continuing stirring at the oil bath temperature overnight after the dripping is finished, filtering the obtained solid-liquid mixture, and collecting the 1,2, 4-butanetriol product.

2. The process according to claim 1 for the preparation of 1,2, 4-butanetriol by reduction of hydrosilanes, characterized in that: the oil bath temperature in said step (1) was 70 ℃.

3. The process according to claim 1 for the preparation of 1,2, 4-butanetriol by reduction of hydrosilanes, characterized in that: the volume ratio of the methanol-potassium hydroxide solution in the step (2) is 1: 1.

4. The process according to claim 1 for the preparation of 1,2, 4-butanetriol by reduction of hydrosilanes, characterized in that: the concentration of the potassium hydroxide in the step (2) is 1 mol/L.

Technical Field

The invention relates to a method for preparing 1,2, 4-butanetriol by reducing hydrosilane.

Background

1,2, 4-Butanetriol (BT) is an important chemical intermediate, has similar application to glycerin, and can be used as a wetting agent, a solvent and an intermediate for producing medicines and explosives. But the development of the product is influenced because the price is difficult to compete with the glycerol.

Since the first synthesis in 1894, 1,2, 4-Butanetriol (BT) has been synthesized in various ways depending on the selection of raw materials, the type of catalyst, and the reaction conditions. For example, butenol is used as a raw material, tungstic acid is used as a catalyst, and the BT is prepared by a direct oxidation method of hydrogen peroxide; if butynediol is taken as a raw material, a mercury catalytic hydration and hydrogenation two-step method is adopted; 2-butylene-1, 4-diol is taken as a raw material, and is subjected to epoxidation and hydrogenolysis; using malic acid diester as raw material, passing through NaBH₄BT can be prepared by reduction method and other methods.

Wherein the appleThe acid diester reduction method is reported in the United kingdom by Africa Limited in its national patent (ZL97198976.1) using NaBH in an ether and an alcohol₄Reduction, which can be carried out at room temperature, but requires large amounts of NaBH₄And the generated by-products are very stable and are not beneficial to recycling.

A large number of methods have been reported in which 2-butene-1, 4-diol is used as a raw material and epoxidation-hydrogenolysis is employed. For example, 2-butene-1, 4-diol in H is reported in JP59070632 by the company MTC of Japan₂WO₄Epoxidizing in the presence of N-methylmorpholine, and then carrying out hydrogenolysis in the presence of a Pd catalyst to obtain BT; the institute of chemical and physical university of Chinese academy of sciences reports that the BT is obtained by epoxidizing butenediol in the presence of phosphotungstic heteropoly acid salt catalyst and then carrying out hydrogenolysis in the presence of Raney nickel-Pd/C catalyst. However, the epoxidation-hydrogenolysis method generally requires a large amount of noble metal catalyst or raney nickel and a large hydrogen pressure, and the reaction conditions are relatively severe.

The process for synthesizing BT by adopting butynediol hydration and hydrogenolysis needs to use a mercury-based catalyst, and the environment is seriously polluted.

Disclosure of Invention

In view of the shortcomings of the prior art, the invention aims to disclose a method for preparing 1,2, 4-butanetriol by reducing hydrosilane.

In order to achieve the purpose, the technical scheme adopted by the invention is to prepare butanetriol by reducing dimethyl malate by using polymethylhydrosiloxane under the catalysis condition of potassium tert-butoxide, and the method comprises the following specific steps:

1. a method for preparing 1,2, 4-butanetriol by reducing hydrosilane is characterized by comprising the following steps: the method comprises the following steps:

(1) putting a certain mass of dimethyl malate, polymethylhydrosiloxane and a certain volume of 1, 4-dioxane into a single-mouth round-bottom flask, uniformly mixing, adding a certain mass of potassium tert-butoxide under stirring, and reacting for 48 hours in a constant-temperature oil bath.

(2) After the reaction in the step (1) is finished, slowly dripping a certain volume of methanol-potassium hydroxide solution into the reaction system to stop the reaction, continuing stirring at the oil bath temperature overnight after the dripping is finished, filtering the obtained solid-liquid mixture, and collecting the 1,2, 4-butanetriol product.

2. The process according to claim 1 for the preparation of 1,2, 4-butanetriol by reduction of hydrosilanes, characterized in that: the oil bath temperature in said step (1) was 70 ℃.

3. The process according to claim 1 for the preparation of 1,2, 4-butanetriol by reduction of hydrosilanes, characterized in that: the volume ratio of the methanol-potassium hydroxide solution in the step (2) is 1: 1.

4. The process according to claim 1 for the preparation of 1,2, 4-butanetriol by reduction of hydrosilanes, characterized in that: the concentration of the potassium hydroxide in the step (2) is 1 mol/L.

The method has the advantages of low price of reducing agent, mild reaction conditions, 100% of selectivity of 1,2, 4-butanetriol and 70% of yield.

Detailed Description

The present invention will be further explained with reference to specific examples, but the present invention is not limited to the following embodiments.