CN102351689A - Preparation technique of p-hydroxy-cinnamic acid - Google Patents

Abstract

The invention discloses a preparation technique of p-hydroxy-cinnamic acid, which comprises the following steps: carrying out reaction on p-hydroxy-benzaldehyde, which serves as the main raw material, under the catalytic action of sodium methoxide by using ethyl acetate as a solvent, thereby implementing experimentation and production by a one-step process; and after the reaction finishes, recycling the ethyl acetate, and carrying out alkali dissolution and acid precipitation to obtain the finished product, wherein the product purity is higher than 99%, and the mol yield is higher than 90%.

Description

A kind of preparation technology of p-Coumaric Acid

Technical field

The present invention is specifically related to a kind of preparation technology of p-Coumaric Acid.

Background technology

P-Coumaric Acid (P-Hydroxycinnamic acid) is claimed P-coumaric acid again.Extensively be present in the natural plant, especially in the majority with leguminous plants content.P-Coumaric Acid is widely used in chemical fields such as medicine, food, daily necessities, feed.Aspect medical, big quantity research shows that p-Coumaric Acid has very strong biological activity; Rise effects such as white like anti-oxidant, antitumor, anti-chemotherapy; Still sharp simultaneously effective constituent, its choleretic effect is close with the acid of equivalent dehydrogenation oxygen, and has the persistent advantage of effect mitigation; Also can be used as and produce the satisfying fixed midbody of therapeutic drug of coronary heart disease, and be used to make local anesthetic, sterilant and styptic etc.P-Coumaric Acid is very important essence and flavoring agent, still is a kind of electro-conductive material of strong effect simultaneously, and the application in liquid-crystal display technology is also by broad research in recent years.In recent years, also be devoted to the research of p-Coumaric Acid is expanded to mikrobe and medical field both at home and abroad--the influence of-cytodifferentiation and telomerase activation, to restraining effect of cervical cancer etc.In the future, p-Coumaric Acid can get more and more to such an extent that be applied in our life.

P-Coumaric Acid preparation technology in the past mainly contains following several kinds:

1. natural extract method difficulty is big, cost is high, and productive rate is extremely low;

2. adopting PARA HYDROXY BENZALDEHYDE and propanedioic acid in the past the synthesis technique is raw material, react according to Knoevenagel-doebner and synthesized p-Coumaric Acid, but yield is low, and yield is merely 50%;

3. react under microwave condition with PARA HYDROXY BENZALDEHYDE and propanedioic acid, pyridine, piperidines, though yield has raising, but the corresponding raising of raw-material cost realizes that suitability for industrialized production is comparatively complicated.

Summary of the invention

The preparation technology who the purpose of this invention is to provide the p-Coumaric Acid that a kind of cost is low, purity is high, yield is high, the reaction times is short.

 

The technical scheme of taking for the present invention that achieves the above object is:

A kind of preparation technology of p-Coumaric Acid comprises the steps:

(1) in reaction vessel, add ETHYLE ACETATE 700ml, PARA HYDROXY BENZALDEHYDE 97.6g stirs, cooling;

(2) when temperature drops to 10-30 ℃, begin to add sodium methylate 150g, controlled temperature 20-50 ℃, stir insulation between 20-50 ℃ behind the adding sodium methylate;

(3) after insulation finishes, add entry 200-500ml, fully stir, begin distillation, until distilling to 99 ℃;

(4) distillation cools to below 50 ℃ after finishing, and slowly adds 20% liquid caustic soda 600ml, and reheat is warmed up to backflow, insulation; Be cooled to 60 ℃ after insulation finishes, beginning slowly drips 30% hydrochloric acid, transfers PH=1, cools to below 40 ℃, filters, and washing is drained, drying; Get the p-Coumaric Acid finished product.

Wherein, soaking time is 8 hours in (2).

Wherein, churning time is 15-30 minute in (3).

Wherein, soaking time is 2 hours in (4).

 

Among the present invention, being main raw material with the PARA HYDROXY BENZALDEHYDE, is solvent with ETHYLE ACETATE; Under the catalysis of sodium methylate, react, make an experiment and produce with the mode of single stage method, reaction finishes ETHYLE ACETATE is recycled; Carrying out alkali then dissolves; Acid out obtains finished product, and product purity is more than 99%, and molar yield reaches more than 90%.

Major advantage of the present invention:

1, this technology is raw material with the ETHYLE ACETATE of cheapness, and wide material sources are easy to buying;

With the inexpensive sodium methylate that is prone to purchase is catalyzer, can reduce cost; Raw materials cost is merely 2/3 of conventional production process;

2, the synthetic yield is high;

3, the time of reaction is short;

4, the solvent boiling point that uses is low, and distillation is recycled easily, cut down the consumption of energy, thereby

Reduce production costs.

 

Embodiment

Following examples are used to explain the present invention, but are not used for limiting scope of the present invention.

Embodiment 1:In the four-hole boiling flask of 2000ml, add ETHYLE ACETATE 700ml, right

Hydroxy benzaldehyde 97.6g opens stirring, cooling., temperature begins to add sodium methylate 150g when dropping to 10-30 ℃, controlled temperature 20-50 ℃.Add the back and stir, insulation is 8 hours between 20-50 ℃, after end reaction insulation finishes, adds entry 200-500ml, stirs 15 minutes, begins distillation, begins cut during 65 ℃ of left and right sides, until distilling to 99 ℃.Distillation cools to below 50 ℃ after finishing, and slowly adds 20% liquid caustic soda 600ml, and reheat is warmed up to backflow, is incubated 2 hours.Insulation finishes 60 ℃ of back coolings, and beginning slowly drips 30% hydrochloric acid, transfers PH=1, cools to below 40 ℃, filters, and filter cake washs with clear water, drains.But harvest article 110-125g after the drying, content are more than 99%, and outward appearance is the crystallization of off-white color to white powder, 208 ℃ of fusing points.

 

Product is analyzed with Tianjin, island high performance liquid chromatograph, and analysis condition is following, and moving phase is the mixed solution of first alcohol and water, methyl alcohol: water=60:40, column type: C18 250 * 4.6 * 5 μ m, wavelength: 230nm, flow velocity: 1ml/min.Take by weighing the 0.01g dry product and be diluted to the 10ml volumetric flask, sample introduction 10 μ l with moving phase.Analytical results shows: the content of p-Coumaric Acid reaches 99.20%.

Claims (4)

1. the preparation technology of a p-Coumaric Acid is characterized in that, comprises the steps:

(1) in reaction vessel, add ETHYLE ACETATE 700ml, PARA HYDROXY BENZALDEHYDE 97.6g stirs, cooling;

(2) when temperature drops to 10-30 ℃, begin to add sodium methylate 150g, controlled temperature 20-50 ℃, stir insulation between 20-50 ℃ behind the adding sodium methylate;

(3) after insulation finishes, add entry 200-500ml, fully stir, begin distillation, until distilling to 99 ℃;

(4) distillation cools to below 50 ℃ after finishing, and slowly adds 20% liquid caustic soda 600ml, and reheat is warmed up to backflow, insulation; Be cooled to 60 ℃ after insulation finishes, beginning slowly drips 30% hydrochloric acid, transfers PH=1, cools to below 40 ℃, filters, and washing is drained, drying; Get the p-Coumaric Acid finished product.

2. preparation technology as claimed in claim 1 is characterized in that, soaking time is 8 hours in (2).

3. preparation technology as claimed in claim 1 is characterized in that, churning time is 15-30 minute in (3).

4. preparation technology as claimed in claim 1 is characterized in that, soaking time is 2 hours in (4).