CN1150994C - L-sulforamidate type chiral ionic liquid and its prepn - Google Patents

Abstract

The invention relates to a novel L-amino acid sulfate-type chiral ionic liquid and a preparation method thereof, and belongs to the technical field of new chemical materials and preparation thereof. Prepare an aqueous solution of L-amino acid and fully react with sulfuric acid with a concentration of 98% to obtain an amino acid sulfate type chiral ionic liquid. The prepared amino acid sulfate chiral ionic liquid not only has the characteristics of ionic liquid but also has the characteristics of chiral substances, and no pollutants are discharged during the reaction, no by-products, high product purity, low cost, suitable for large-scale industrialization Production application is likely to become an important new material in green chemical industry in the future.

Description

L-amino acid sulfate type chiral ionic liquid and preparation method thereof

(1) Technical field

The invention relates to an ionic liquid and a preparation method thereof, in particular to a novel L-amino acid sulfate type chiral ionic liquid and a preparation method of the chiral ionic liquid, belonging to the technical field of new chemical materials and its preparation.

(2) Background technology

In recent years, ionic liquids have attracted widespread attention as green solvents or catalysts. They are commonly used in some chemical reactions such as organic synthesis, chemical separation, and electrochemistry, and have dual-functional characteristics of solvents and catalysts. Li Ruxiong et al. mentioned in "Chemical Reagents", 2001, 23 (4), pages 211-215, "Synthesis and Application of Ionic Liquids", that there are currently 4 types of cations in ionic liquids: alkyl quaternary ammonium ions, Alkyl quaternary phosphine ions, alkyl imidazolium ions, alkyl pyridinium ions; anions mainly include Cl ^- , Br ^- , BF ₄ ^- , PF ₆ ^- , (CF ₃ SO ₃ ) ₂ N ^- , CF ₃ COO ^- wait. Through different combinations of these cations and anions, ionic liquids with different characteristics can be formulated, but the L-amino acid sulfate type ionic liquid involved in the present invention has not been reported so far. Moreover, these ionic liquids have one thing in common in that the ionic liquids reported in the past do not have the characteristics of chiral substances, that is, they do not have chiral catalytic characteristics, chiral separation characteristics and chiral solvent characteristics, so they are not chiral ions liquid. Chiral substances refer to a class of objects that cannot be superimposed on mirror images. The stereoselectivity of chiral substances based on intramolecular asymmetry induction has played an important role in organic synthetic chemistry, but the so-called chiral substances do not With ionic liquids such as wide range of liquid state, low vapor pressure, good electrical conductivity, wide electrochemical window, strong polarity, and selectivity to the dissolution and catalysis of certain substances. At present, there is no report about the L-amino acid sulfate type chiral ionic liquid, and its preparation method is mentioned for the first time in the present invention. There are also some shortcomings in the preparation of ionic liquids in the past: raw materials are scarce, and the cost is high, generally more than twice that of commonly used organic solvents; preparation is difficult, product purification is difficult, and it is not suitable for large-scale industrial production applications; usually with three The combined use of aluminum chloride is likely to cause pollution and affect its application in green chemical industry.

(3) Contents of the invention

The purpose of the present invention is to provide a kind of L-amino acid sulfate type chiral ionic liquid which not only has the excellent characteristics of chiral substance but also has good characteristics of ionic liquid, and provides the preparation method of this kind of ionic liquid.

The L-amino acid sulfate type chiral ionic liquid provided by the invention has the following structural formula:

[amino acid] _m [SO ₄ ] _n

According to the difference in the valence of different L-amino acid cations, the value range of m is 1-2, and the value range of n is between 1-3, that is, when the valence of the L-amino acid cation is 1, m=2 and n=1 , when the L-amino acid cation valence is 2, m=1 and n=1, when the L-amino acid cation valence is 3, m=2 and n=3, when the L-amino acid cation valence is 4, m=1 and n= 2.

The preparation method of the L-amino acid sulfate type chiral ionic liquid provided by the present invention is: L-amino acid is made into aqueous solution, while stirring, dropwise add the sulfuric acid that concentration is 98%, wherein the mol ratio of L-amino acid and the concentrated sulfuric acid is : When the valence of the L-amino acid cation is 1, the molar ratio is 2:1; when the valence of the L-amino acid cation is 2, the molar ratio is 1:1; when the valence of the L-amino acid cation is 3, the molar ratio is 2: 3. When the valence of the L-amino acid cation is 4, the molar ratio is 1:2. After sufficient reaction, the water is evaporated to obtain the final product L-amino acid sulfate type chiral ionic liquid. The reaction formula is expressed as:

m[amino acid]+nH ₂ SO ₄ →[amino acid] _m [SO ₄ ] _n

The L-amino acid sulfate type chiral ionic liquid involved in the present invention, wherein the L-amino acid [amino acid] is preferably: alanine [Ala], valine [Val], leucine [Leu], glycine [Gly ], tyrosine [Tyr], glutamic acid [Glu], proline [Pro], lysine [Lys], histidine [His] and arginine [Arg]. That is to say, the L-amino acid sulfate chiral ionic liquid involved in the present invention is preferably: alanine sulfate chiral ionic liquid [Ala] ₂ SO ₄ , valine sulfate chiral ionic liquid [Val] ₂ SO _4. Leucine sulfate chiral ionic liquid [Leu] ₂ SO ₄ , glycine sulfate chiral ionic liquid [Gly] ₂ SO ₄ , tyrosine sulfate chiral ionic liquid [Tyr] ₂ SO ₄ , glutamic acid Acid Sulfate Chiral Ionic Liquid [Glu] ₂ SO ₄ , Proline Sulfate Chiral Ionic Liquid [Pro] ₂ SO ₄ , Lysine Sulfate Chiral Ionic Liquid [Lys]SO ₄ , Histidine Sulfate One of chiral ionic liquid [His] ₂ [SO ₄ ] ₃ and arginine sulfate chiral ionic liquid [Arg][SO ₄ ] ₂ .

The preferred scheme of the preparation method of the L-amino acid sulfate type chiral ionic liquid [aminoacid] _m [SO ₄ ] _n described in the present invention is: the L-amino acid in the preparation method is respectively used alanine [Ala], valine [Val], Leucine [Leu], Glycine [Gly], Tyrosine [Tyr], Glutamic Acid [Glu], Proline [Pro], Lysine [Lys], Histidine [His] And one of arginine [Arg] is replaced to obtain the desired prepared L-amino acid sulfate type chiral ionic liquid.

In addition to the above-mentioned sulfates and their preparation, other amino acid sulfates composed of L-amino acids such as tryptophan were also tested. Most of the new compounds have low melting points, generally around -20°C, and a few are below -80°C. Their electrical conductivities measured at 60°C are between 10 ³ -10 ⁴ (unit: μS/cm), which also follow the general law, and the electrical conductivity shows an upward trend with the increase of temperature, and the increase range varies. And at this temperature, the refractive index of the ionic liquid is measured to be between 1.4-1.5. The thermal stability data of a series of new compounds obtained by Mettler’s TG/SDTA851e differential thermal analyzer shows that most of them show good thermal stability and begin to decompose above 200°C, which depends on the properties of various amino acids. characteristic. By using RVT-TB, RVT-TE, RVT2 ^# type viscometers, the measured results at room temperature are between 10 ² -10 ³ cP (except for solid state), and the viscosity varies greatly.

The L-amino acid sulfate chiral ionic liquid provided by the present invention has the following beneficial effects:

(1) It has the characteristics of ionic liquids and chiral substances at the same time, such as: chiral separation, chiral catalysis and characteristics of chiral solvents, etc., and these characteristics are usually not possessed by ionic liquids.

(2) It has the characteristics of chiral substances and the characteristics of ionic liquids, such as: wide liquid range, low vapor pressure, good conductivity, wide electrochemical window, strong polarity, and the dissolution and catalysis of certain substances Selectivity, which is not available in general chiral substances.

The preparation method of the L-amino acid sulfate type chiral ionic liquid provided by the present invention has the following remarkable effects:

(1) The raw materials are relatively easy to obtain and the price is relatively cheap, so the preparation cost is low;

(2) neutralization reaction, simple preparation, less equipment required, and very pure product can be obtained without excessive operation, suitable for large-scale industrial production application;

(3) The preparation process does not discharge pollutants and has no by-products, which belongs to the green preparation process of atomic economy;

(4) The melting point and acid-base strength of the designed product can be adjusted during the preparation process, which was previously only possible with ionic liquids containing aluminum trichloride.

(4) Specific implementation methods

Embodiment 1: Alanine sulfate chiral ionic liquid

Weigh 5.00g of alanine (0.056mol, purity over 99%, purchased by Shanghai Jier Biochemical Co.) into a beaker filled with 50ml of distilled H ₂ O, add 98% H ₂ SO ₄ (analytical pure) dropwise while stirring , the amount of H ₂ SO ₄ is 2.81g (0.028mol), that is, the molar ratio of the reaction raw materials is 2:1, and the transparent mixed solution is stirred at room temperature for 1 hour, then transferred to a rotary evaporator, and the mixture is heated between 40°C and 50°C. The water was evaporated, and then the temperature was raised to 80°C-85°C for evaporation for 2 hours, and finally a colorless and transparent chiral ionic liquid of alanine sulfate was obtained. The reaction formula is:

                  

Embodiment 2: Valine sulfate chiral ionic liquid

Weigh 5.00g of valine (0.043mol, more than 99% purity, purchased by Shanghai Jier Biochemical Co.) into a beaker filled with 50ml of distilled H ₂ O, add 98% H ₂ SO ₄ (analytical pure) dropwise while stirring , the amount of H ₂ SO ₄ was 2.1 g (0.021 mol), that is, the molar ratio of the reaction raw materials was 2:1. Continue to stir the transparent mixture at room temperature for 1 hour, transfer it to a rotary evaporator, evaporate water at 40°C-50°C, then heat up to 80°C-85°C for 2 hours, and finally obtain a colorless transparent valine Sulfate chiral ionic liquid. The reaction formula is:

                

Embodiment 3: leucine sulfate chiral ionic liquid

Weigh 5.00g of leucine (0.038mol, purity over 99%, purchased from Shanghai Jill Biochemical _Co. ) into a beaker filled with 50ml of distilled _H2O , and add 98% _H2SO4 (analytical pure) dropwise while stirring , the amount of H ₂ SO ₄ was 1.9 g (0.019 mol), that is, the molar ratio of the reaction raw materials was 2:1. Continue to stir the transparent mixture at room temperature for 1 hour, transfer it to a rotary evaporator, evaporate water at 40°C-50°C, then heat up to 80°C-85°C for 2 hours, and finally obtain a colorless transparent leucine Sulfate chiral ionic liquid. The reaction formula is:

                

Embodiment 4: glycine sulfate chiral ionic liquid

Weigh 5.00g of glycine (0.067mol, more than 99% purity, purchased by Shanghai Jier Biochemical Co., Ltd.) and put it into a beaker filled with 50ml of distilled H ₂ O, and add 98% H ₂ SO ₄ (analytical pure) dropwise while stirring, H The amount of ₂ SO ₄ used was 3.3 g (0.033 mol), that is, the molar ratio of the reaction raw materials was 2:1. The clear mixture was stirred for an additional 1 hour at room temperature. Transfer to a rotary evaporator, evaporate water at 40°C-50°C, then heat up to 80°C-85°C for 3 hours, and finally obtain a colorless transparent liquid glycine sulfate chiral ionic liquid. The reaction formula is:

                

Embodiment 5: Tyrosine sulfate chiral ionic liquid

Weigh 5.00g of tyrosine (0.028mol, more than 99% purity, purchased by Shanghai Jier Biochemical Co., Ltd.) into a beaker filled with 50ml of distilled H ₂ O, and add 98% H ₂ SO ₄ (analytical pure) dropwise while stirring. , the amount of H ₂ SO ₄ was 1.4 g (0.014 mol), that is, the molar ratio of the reaction raw materials was 2:1. Continue to stir the transparent mixture at room temperature for 1 hour, transfer it to a rotary evaporator, evaporate water at 40-50°C, then heat up to 80-85°C and evaporate for 2 hours, and the final product is cooled and crystallized to obtain tyrosine sulfate. Sexual ionic liquids. The reaction formula is:

               

Embodiment 6: glutamic acid sulfate chiral ionic liquid

Weigh 5.00g of glutamic acid (0.034mol, purity above 99%, purchased by Shanghai Jier Biochemical Company) and put it into a beaker filled with 50ml of distilled H ₂ O, add 98% H ₂ SO ₄ (analytical pure) dropwise while stirring , the amount of H ₂ SO ₄ was 1.7 g (0.017 mol), that is, the molar ratio of the reaction raw materials was 2:1. Continue to stir the transparent mixture at room temperature for 1 hour, transfer to a rotary evaporator, evaporate water at 40°C-50°C, then heat up to 80°C-85°C for 2 hours, and finally obtain a colorless transparent glutamic acid Sulfate chiral ionic liquid. The reaction formula is:

                

Embodiment 7: proline sulfate chiral ionic liquid

Weigh 5.00g of proline (0.043mol, purity over 99%, purchased by Shanghai Jier Biochemical Co.) into a beaker filled with 50ml of distilled H ₂ O, add 98% H ₂ SO ₄ (analytical pure) dropwise while stirring , the amount of H ₂ SO ₄ was 2.1 g (0.021 mol), that is, the molar ratio of the reaction raw materials was 2:1. Continue to stir the transparent mixture at room temperature for 1 hour, transfer to a rotary evaporator, evaporate water at 40°C-50°C, then heat up to 80°C-85°C for 3 hours, and finally obtain a colorless transparent proline Sulfate chiral ionic liquid. The reaction formula is:

                

Embodiment 8: Lysine sulfate chiral ionic liquid

Weigh 5.00g of lysine (0.034mol, more than 99% purity, purchased by Shanghai Jier Biochemical Company) and put it into a beaker filled _with 50ml of distilled H2O, and add 98% _H2SO4 (analytical pure) dropwise while stirring, H The amount of ₂ SO ₄ used is 3.4 g (0.034 mol), that is, the molar ratio of the reaction raw materials is 1:1. Continue to stir the transparent mixture at room temperature for 1 hour, transfer to a rotary evaporator, evaporate water at 40°C-50°C, then heat up to 80°C-85°C for 2 hours, and finally obtain a colorless transparent lysine Sulfate chiral ionic liquid. The reaction formula is:

                 

Embodiment 9: histidine sulfate chiral ionic liquid

Weigh 5.00 g of arginine (0.032 mol, with a purity of more than 99%, purchased by Shanghai Jier Biochemical Co., Ltd.) and put it into a beaker filled with 50 ml of distilled H ₂ O, and add 98% H ₂ SO ₄ (analytical pure) dropwise while stirring. , the amount of H ₂ SO ₄ was 4.81 g (0.048 mol), that is, the molar ratio of the reaction raw materials was 2:3. Continue to stir the transparent mixture at room temperature for 1 hour, transfer it to a rotary evaporator, evaporate water at 40°C-50°C, then heat up to 80°C-85°C for 2 hours, and finally obtain a colorless transparent histidine Sulfate chiral ionic liquid. The reaction formula is:

              

Embodiment 10: Arginine sulfate chiral ionic liquid

Weigh 5.00g of arginine (0.029mol, more than 99% purity, purchased by Shanghai Jier Biochemical Co., Ltd.) into a beaker filled with 50ml of distilled H ₂ O, and add 98% H ₂ SO ₄ (analytical pure) dropwise while stirring. , the amount of H ₂ SO ₄ was 5.6 g (0.056 mol), that is, the molar ratio of the reaction raw materials was 1:2. Continue to stir the transparent mixture at room temperature for 1 hour, transfer it to a rotary evaporator, evaporate water at 40°C-50°C, then heat up to 80°C-85°C for 2 hours, and finally obtain a colorless transparent arginine Sulfate chiral ionic liquid. The reaction formula is:

                

The L-amino acid sulfate chiral ionic liquid involved in the present invention, because the preparation process belongs to a simple acid-base neutralization reaction, does not discharge pollutants, has no by-products, and can obtain very pure products without excessive operations, and the cost is relatively low. Low, suitable for large-scale industrial production and application, it is likely to become an important new material in green chemical industry in the future.

Claims (4)

1, a kind of L-amino acid sulfate type chiral ionic liquid, it is characterized in that structural formula is as follows: [amino acid] _m [SO ₄ ] _n According to the difference in the valence of different L-amino acid cations, the value range of m is 1-2, and the value range of n is between 1-3, that is, when the valence of the L-amino acid cation is 1, m=2 and n=1 , when the L-amino acid cation valence is 2, m=1 and n=1, when the L-amino acid cation valence is 3, m=2 and n=3, when the L-amino acid cation valence is 4, m=1 and n= 2. 2. The L-amino acid sulfate type chiral ionic liquid as claimed in claim 1, characterized in that said L-amino acid ion is: alanine ion, valine ion, leucine ion, glycine ion, tyrosine ion One of acid ion, glutamate ion, proline ion, lysine ion, histidine ion and arginine ion. 3. A method for preparing an L-amino acid sulfate type chiral ionic liquid, characterized in that the preparation process is as follows: Prepare amino acid into aqueous solution, and add sulfuric acid with a concentration of 98% dropwise while stirring, wherein the molar ratio of L-amino acid to concentrated sulfuric acid is: when the valence of L-amino acid cation is 1, the molar ratio is 2:1, when L- When the valence of the amino acid cation is 2, the molar ratio is 1:1; when the valence of the L-amino acid cation is 3, the molar ratio is 2:3; when the valence of the L-amino acid cation is 4, the molar ratio is 1:2, fully reacting Finally, the water is evaporated to obtain the final product L-amino acid sulfate type chiral ionic liquid. 4. The preparation method of L-amino acid sulfate type chiral ionic liquid as claimed in claim 3, characterized in that said L-amino acid is selected from alanine, valine, leucine, glycine, tyrosine, glutamic acid One of amino acid, proline, lysine, histidine and arginine.