KR101088197B1 - Heterogeneous metal catalyst for synthesis of furan derivatives and method of manufacturing thereof - Google Patents

Abstract

The present invention relates to a heterogeneous metal catalyst for synthesizing a furan-based compound and a method for preparing the same, wherein the heterogeneous metal catalyst for synthesizing a furan-based compound is represented by the following general formula (I), and is composed of a polymer resin and an imidazole compound It includes an imidazole ligand, the metal element is coordinated to the imidazole ligand.

<Formula I>

In formula (I), R is an alkyl group or mesityl group with or without a hetero atom, and M is a metal element.

According to the present invention, after completion of the reaction, separation and purification of the metal catalyst material is easy and the catalyst activity by the imidazole ligand is excellent.

In addition, according to the present invention, there is an economic benefit through the reuse of the catalyst and the application to the continuous reaction process.

Heterogeneous catalyst, fructose, imidazole, polymer resin, polystyrene, HMF, hexasaccharide

Description

Heterogeneous metal catalyst for synthesizing furan-based compounds, and a method for manufacturing the same {HETEROGENEOUS METAL CATALYST FOR SYNTHESIS OF FURAN DERIVATIVES AND METHOD OF MANUFACTURING THEREOF}

The present invention relates to a heterogeneous metal catalyst for synthesizing a furan-based compound and a method for producing the same, and more particularly, a furan-based compound capable of synthesizing a furan-based compound by dehydration catalysis using a hexasaccharide material derived from biomass. A heterogeneous metal catalyst for synthesizing a compound and a method for producing the same.

Due to the recent limited supply of crude oil and supply and demand imbalances due to the emergence of emerging developing countries, instability of international oil prices is increasing in the future, and the cost of irreversible CO2 emissions through global environmental regulations is a concern for renewable resources that can be used instead of fossil resources. It is increasing.

Currently, crude oil is converted into fuel materials such as gasoline and diesel through refining process and used for power generation and transportation, or as raw material of various compounds through naphtha cracking process. Especially, aromatic, which is a key raw material of omnidirectional chemical industry, is used. Almost all of the compounds are obtained from petroleum.

Recently, a furan-based compound has received much attention as a candidate material for replacing such petroleum-based aromatic compounds. Furan-based compounds (or furan derivatives), such as 5-hydroxymethylfurfural (HMF) and furfural, are obtained from carbohydrates derived from renewable biomass and are based on petroleum used in fine chemical and plastic products. As a result, it has a great potential to continuously replace an industrial raw material, and research and development on various conversion reactions have been made in this regard.

Among the furan compounds, 5-hydroxymethylfurfural (HMF) shown in the following structural formula is a conversion product of hexasaccharides having 6 carbon atoms, hexasaccharides carbohydrates such as fructose and glucose, or Intermediate platform material that can be obtained from natural carbohydrates such as sugar and starch or renewable biomass-derived carbohydrate including them, and widely used as monomers, adhesives, adhesives, coatings, etc. of bio-based plastics through various conversion reactions. There is a lot of research on how to make it possible to mass produce it.

Structural Formula of HMF

또는

or

In order to convert the hexasaccharides obtained from the carbohydrate-based biomass through pretreatment and monosaccharide fermentation into 5-hydroxymethylfurfural, for example, HMF (2) from D-fructose (1) is obtained. As shown in the reaction scheme, three equivalents of water molecules must be selectively removed from one equivalent of hexavalent sugar molecules by dehydration, which requires the use of an acid catalyst.

[Scheme of Dehydration of D-Fructose]

It is most common to use traditional inorganic acid catalysts such as sulfuric acid and hydrochloric acid as acid catalysts, and Lewis acid catalysts in which various ligands are coordinated with metals for the purpose of increasing activity and selectivity. However, there is a problem in that as a homogeneous catalyst, waste acid or hazardous metal substance should be removed at the end of the reaction. Therefore, heterogeneous solid acid catalysts are often used to solve the problem of separation and purification, and to facilitate reuse and use in continuous processes. However, since the solid acid catalyst has a low reaction rate due to a heterogeneous reaction and the compatibility between the reactant and the catalyst support is poor, it is necessary to make an effort to increase the activity as much as possible.

As a representative example, the Dumesic group is a technique for obtaining 5-hydromethylmethylfurfural at a conversion rate of 90% from fructose by conducting a study to separate the product from the reaction mixture in a biphasic condition to increase the yield and selectivity. (Yuriy Roman-Leshkov, Juben N. Chheda, James A. Dumeic, Science , 2006 , 312 , 1933-1937), Zhang group of PNNL used 83% conversion from glucose using chromium catalysts in ionic liquids. 5-hydromethylmethylfurfural has been obtained (Haibo Zhao, Johnathan E. Holladay, Heather Brown, Z. Conrad Zhang, Science , 2007 , 316 , 1597-1600). In addition, HE van Dam et al. Proposed a method of obtaining 5-hydromethylmethylfurfural from fructose using p-Toluenesulfonic acid as a catalyst (HE van Dam, Dr. APG Kieboom, Prof. H. van Bekkum, Delft University of Technology, Laboratory of Organic Chemistry, Starch , 2006 , Volume 38 Issue 3, Pages 95-101).

 However, all of the above results are the conversion rate observed on the chromatograph, which excludes the purification process of the final product by the use of homogeneous catalysts or is an economical aspect for scale-up due to the use of expensive materials such as ionic liquids. I am having a problem.

Therefore, there is an urgent need to develop a new conversion reaction that can easily separate and purify the final product and efficiently produce 5-hydroxymethylfurfural on an industrial scale without using expensive materials.

The present invention is to solve the above problems, an object of the present invention is the difficulty of the separation and purification process by easily removing the metal catalyst used in the reaction process to obtain a furan-based compound from the hexasaccharide carbohydrate derived from biomass with a filter after the reaction termination And to convert the ionic liquid material into a solid phase, thereby providing a heterogeneous metal catalyst with maximized activity.

In addition, an object of the present invention is to provide a catalyst that maximizes the economy by using a heterogeneous metal catalyst that can be reused and can be easily used in a continuous reaction process.

The present invention is to solve the above problems, the heterogeneous metal catalyst for synthesizing the furan-based compound according to the present invention is represented by the following formula (I), and comprises a solid imidazole ligand consisting of a polymer resin, an imidazole compound, The metal element is coordinated with the imidazole ligand.

<Formula I>

In formula (I), R is an alkyl group or mesityl group with or without a hetero atom, and M is a metal element.

The heterogeneous metal catalyst for synthesizing furan compound according to the present invention having such a structure is an imidazole compound such as N-methylimidazole, which is known to be able to increase the activity of the catalyst as a ligand of a metal element in a bead made of a polymer resin. Is introduced through a covalent bond in a solid phase organic synthesis reaction, and then the metal element is coordinated with the imidazole ligand, thereby converting the imidazole compound, which is a conventional ionic liquid substance, into a solid phase, and is a heterogeneous catalyst that is easily separated and purified after completion of the reaction. In the form of a catalyst, and also improves catalytic activity.

Specifically, the polymer resin is not particularly limited, but preferably, the structure of the heterogeneous catalyst when methyl imidazole is applied as the imidazole compound to which polystyrene is applied and connected thereto is as shown in the general formula (II).

<Formula II>

In addition, the metal element is selected from the group consisting of transition metal, alkali metal, lanthanum metal, and mercury (Hg). Preferably, the transition metal is any one of Cr, Mn, Fe, Co, Ni, Cu, Zn, Au, Ru, Rh, and Pt, the alkali metal is Li or Rb, and the lanthanum metal is La, Ce , Nd. In addition, in addition to the metal element, Lewis acids such as AlCl ₃ or sulfuric acid (H ₂ SO ₄ ) and the like may be preferably applied.

When 5-hydromethylmethylfurfural is synthesized by using a heterogeneous metal catalyst for synthesizing a furan-based compound having the above-described structure as a catalyst for the dehydration reaction of fructose, as shown in the following examples, In the yield of 90% or more, the desired substance, 5-hydromethylmethylfurfural, can be obtained.

Next, a method for preparing a heterogeneous metal catalyst for synthesizing the furan-based compound according to the present invention will be described.

In the method for producing a heterogeneous metal catalyst for synthesizing a furan-based compound according to the present invention, a polymer resin containing a halogen group at a terminal is reacted with an imidazole compound, and the halogen group is substituted with an imidazole compound as shown in Scheme I below. A precursor preparing step of preparing a polymer resin-imidazole compound catalyst precursor covalently linked; And a catalyst preparing step of preparing a metal catalyst of Chemical Formula I by coordinating a metal element using the polymer resin-alkylimidazole compound as a ligand as shown in Scheme II.

<Scheme I>

<Scheme II>

In Schemes I and II, R is an alkyl group or mesityl group containing or not containing a hetero atom, and X, X ₁ , and X ₂ are each independently selected from the group consisting of F, Cl, Br or I Halogen group.

As a specific example of this, according to the method for producing a heterogeneous metal catalyst for synthesizing a furan compound according to an embodiment of the present invention, on the chloromethyl polystyrene resin beads as the polymer resin, it acts as a ligand of a metal element as an imidazole compound N-methylimidazole, which is known to increase the activity of the catalyst, is introduced through a covalent bond in a solid phase organic synthesis reaction to prepare a catalyst precursor, and then the metal catalyst is coordinated using the catalyst precursor as a ligand in an organic solvent. To prepare various heterogeneous metal catalysts.

More specifically, the precursor manufacturing step, after swelling the polymer resin in an organic solvent, the imidazole compound is added by stirring, washing, drying and the step of preparing a catalyst, the polymer resin step, After swelling the imidazole compound in an organic solvent, any one of metal compounds of halogenated metals and sodium compounds, potassium compounds, lithium compounds, and magnesium compounds formed by halogenation of the metal elements is added, stirred, washed, and dried. It can be made to the step.

Here, the organic solvent used in the precursor preparation step and the catalyst preparation step, preferably N-methylpyrrolidone (NMP), dimethyl sulfoxide (DMSO), dimethylformamide (DMF), tetrahydrofuran (THF) , Hydrophobic or hydrophilic solvents such as ether, dimethoxyethane, nitromethane, hexane, toluene, dichloromethane, chloroform, dioxane, acetonitrile, water, ethanol, methanol, and the like, in particular, each precursor preparation step The use of N-methylpyrrolidone (NMP) and dimethyl sulfoxide (DMSO) in the catalyst preparation stage showed the best catalyst yield.

In addition, the metal compound used in the catalyst preparation step is secondary to the catalyst precursor, ie, imidazole ligand, generated through the halogen substitution reaction in the precursor preparation step, thereby improving the polarity, thereby coordinating the catalyst precursor as a ligand. It is applied to give a strong bond with a metal element, and such a metal compound can be used without particular limitation, as long as it can produce a strong bond with a metal element by adjusting the polarity of the catalyst precursor.

In the present invention, as such a metal compound, a metal compound containing an element periodic metal of Group 1A or a Group 2A metal can be used. Specifically, as described above, any one of a sodium compound, potassium compound, lithium compound, and magnesium compound can be used.

As an example of the sodium compound, sodium acetate, sodium acrylate, sodium amide, sodium benzoate, sodium tetrabutoxide, sodium chlorate, sodium chloroacetate, sodium cyanate, sodium cyanide, sodium cyclohexane butyrate, sodium Dichloroacetate, sodium ethoxide, sodium ethane acrylate, sodium formate, sodium hydrochloride, sodium methacrylate, sodium octanoate, sodium periodate, sodium propionate sodium iodate, sodium iodoacetate, sodium 3 Any one selected from -chlorodifluoroacetate can be used.

Examples of the potassium compound include potassium acetate, potassium acrylate, potassium amide, potassium benzoate, potassium tetrabutoxide, potassium chlorate, potassium chloroacetate, potassium cyanate, potassium cyanide, potassium cyclohexanebutylate, potassium dichloro Acetate, Potassium Ethoxide, Potassium Ethane Eylate, Potassium Formate, Potassium Hydrochloride, Potassium Methacrylate, Potassium Octanoate, Potassium Periodate, Potassium Propionate, Potassium Iodide, Potassium Iodoacetate, Potassium 3 Any one selected from -chlorodifluoroacetate can be used.

Examples of the lithium compound include lithium acetate, lithium acrylate, lithium amide, lithium benzoate, lithium tetrabutoxide, lithium chlorate, lithium chloracetate, lithium cyanate, lithium cyanide, lithium cyclohexanebutyrate, lithium Dichloroacetate, lithium ethoxide, lithium ethane acrylate, lithium formate, lithium hydrochloride, lithium methacrylate, lithium octanoate, lithium periodate, lithium propionate, lithium iodate, lithium iodoacetate, lithium Any one selected from 3-chlorodifluoroacetate can be used.

As an example of the magnesium compound, magnesium acetate, magnesium acrylate, magnesium amide, magnesium benzoate, magnesium tetrabutoxide, magnesium chlorate, magnesium chloroacetate, magnesium cyanate, magnesium cyanide, magnesium cyclohexanebutyrate, magnesium dichloroacetate , Magnesium ethoxide, magnesium ethane acrylate, magnesium formate, magnesium hydrochloride, magnesium methacrylate, magnesium octanoate, magnesium periodate, magnesium propionate, magnesium iodate, magnesium iodoacetate, magnesium 3- Any one selected from chlorodifluoroacetate can be used. Here, the metal compound is preferably added in a small amount of 0.01 to 1 equivalent relative to the catalyst precursor equivalent.

5-hydroxymethylfurfural (HMF) can be obtained by reacting hexasaccharide carbohydrates derived from biomass using a heterogeneous metal catalyst for synthesizing furan compounds obtained by the above production method. For example, the process of converting fructose to HMF as the hexasaccharide is as shown in Scheme III.

<Scheme III>

According to the present invention, after completion of the reaction, separation and purification of the metal catalyst material is easy and the catalyst activity by the imidazole ligand is excellent.

In addition, according to the present invention, there is an economic benefit through the reuse of the catalyst and the application to the continuous reaction process.

Hereinafter, the heterogeneous metal catalyst for synthesizing furan compound according to the present invention and a method for producing the same will be described.

Manufacturing example  One

Immobilized on polystyrene Imidazolium  Preparation of Chloride

As shown in Scheme I-1, 1 g chloromethyl polystyrene resin (CMPS, Merrifield resin 1% crosslinking, 100-200 mesh, 4.2 mmol / g) was swollen to N-methylpyrrolidone. After 2 equivalents of N-methylimidazole was added and stirred at 80 ° C. for about 24 hours, the resin obtained by filtration was washed sequentially with N, N-dimethylformamide, water, acetone, methanol, and the like. And dried under vacuum to obtain a methyl imidazole bound resin (3.2 mmol / g).

<Scheme I-1>

Manufacturing example  2

Preparation of Metal Catalysts Immobilized on Polystyrene

As shown in Scheme II-1, the resin obtained in Preparation Example 1 was swelled in dimethyl sulfoxide (DMSO) and reacted at 60 ° C. for 8 hours, and then 0.1 equivalent of potassium tetrabutoxide was added as a metal compound, followed by transition After adding a metal catalyst such as Lewis acid or mineral acid to which metal chlorides such as metals, alkali metals and lanthanide metals or chlorine ions are bound, and reacting at 80 ° C. for 30 minutes, the reaction product is filtered, and N, It was washed with N-dimethylformamide, water, acetone, methanol and the like and dried to obtain a polystyrene support bonded with a metal catalyst.

<Scheme II-1>

Manufacturing example  3

Using polystyrene support fixed with metal catalyst Of fructose Dehydration  reaction

The heterogeneous metal catalyst for synthesizing the furan-based compound prepared by the above-described method was used as a catalyst for dehydration to convert biomass-derived fructose into 5-hydroxymethylfurfural. As shown in Scheme III-1, dimethyl sulfoxide (DMSO) was added after adding fructose (0.5 mmol) using the polystyrene support (5 mol%) to which the metal catalyst obtained in Preparation Example 2 was bonded as a heterogeneous metal catalyst. 2 mL of the solvent was stirred at 100 ° C. for 1 hour.

<Scheme III-1>

Experimental Example  One

The reaction step according to each preparation was able to determine the progress of the reaction by confirming the formation and disappearance of chemical bonds through FT-IR. This is shown in FIG. The horizontal axis of FIG. 1 is the wavelength (nm), the vertical axis represents the transmission intensity, and as shown in FIG. 1, the binding of [B] CMPS and imidazole through [substitution] reaction from [A] chloromethyl polystyrene resin (CMPS) As the reaction proceeds to (CMPS-IM) and to the [C] CMPS-IM-M to which the metal catalyst is bound, the process of transferring the bond can be confirmed.

Experimental Example  2

The individual metal content of the prepared heterogeneous metal catalyst was subjected to elemental analysis through ICP-AES to determine the metal content per weight of the support. This is shown in Table 1.

[Table 1]

Solid phase imidazole ligands
Coordinated Metals (Elemental Symbols) Per gram of resin
Amount of metal contained (μmol / g) Mercury (Hg) 735 Copper (Cu) 619 Ruthenium (Ru) 182 Platinum (Pt) 96 Gold (Au) 33 Rhodium (Rh) 279 Neodymium (Nd) 163 Iron (Fe) 106 Nickel (Ni) 357 Lanthanum (La) 497 Palladium (Pd) 452 Chromium (Cr) 283 Cobalt (Co) 491 Indium (In) 78

Experimental Example  3

The FE-SEM electron microscope and EDX confirmed the surface morphology of the heterogeneous metal catalyst and the metal presence. This is shown in FIG.

Experimental Example  4

The heterogeneous metal catalyst prepared was immersed in a hydrophobic and hydrophilic solvent of hexane, toluene, ether, dichloromethane, THF, chloroform, dioxane, acetonitrile, DMF, NMP, DMSO, water, methanol, and ethanol, respectively, to measure volume expansion coefficient. Swelling was investigated for the solvent. This is shown in FIG. 3 (swelling test for each when supported by chloromethyl polystyrene resin (CMPS) alone and when supported by CMPS-imidazole compound (CMPS-IM)).

Experimental Example  5

After the reaction, the proportion of the product was measured by HPLC analysis of the reaction mixture. It was confirmed that 2,5-furandicarboaldehyde (III-1) and 2,5-bishydroxymethylfuran (III-3) were produced as by-products with 5-hydroxymethylfurfural as a target substance. It was. The ratio of the product to the heterogeneous metal catalyst containing each metal element is shown in Table 2.

<Formula III-1>

<Formula III-2>

Product analysis shows that when heterogeneous metal catalysts including mercury, copper and manganese are used, 5-hydroxymethylfurfural is produced in the highest yield. In particular, it was confirmed that the target substance, 5-hydroxymethylfurfural (5-hydroxymethylfurfural) is obtained with a conversion yield of 90% or more.

TABLE 2

Heterogeneous metal catalyst % Of product 5-hydroxymethylfurfural 2,5-furandicarboaldehyde 2,5-bishydroxymethylfuran Control 74 11 15 Mn 93 7 - Au 91 3 6 Hg 99 - - Cu 94 6 - Ce 91 9 - Ru 75 25 - Pt 91 9 - Al 91 9 - Pd 92 8 -

It has been described in detail above with reference to preferred embodiments of the present invention. However, the scope of the present invention is not limited to the above embodiments, but may be embodied in various forms of embodiments within the appended claims. Without departing from the gist of the invention as claimed in the claims, any person skilled in the art to which the invention pertains is considered to be within the scope of the claims of the invention to the various possible modifications possible.

1 is a step FT-IR measurement graph of the method for producing a heterogeneous metal catalyst for synthesizing a furan-based compound according to a production example of the present invention

2 is an FE-SEM electron microscope and EDX analysis photograph of the heterogeneous metal catalyst for synthesizing furan compound according to the preparation example of the present invention

Figure 3 is a graph showing the swelling of the heterogeneous metal catalyst for synthesizing furan-based compounds according to the preparation of the present invention with respect to the solvent

Claims (9)

A heterogeneous metal catalyst for synthesizing a furan-based compound represented by the following formula (I), comprising a solid imidazole ligand composed of a polymer resin and an imidazole compound, wherein a metal element is coordinated with the imidazole ligand. <Formula I>

In formula (I), R is an alkyl group or mesityl group with or without a hetero atom, and M is a metal element. The method of claim 1, The polymer resin is a polystyrene resin, heterogeneous metal catalyst for synthesizing furan compounds. The method of claim 1, The metal element is a heterogeneous metal catalyst for synthesizing a furan-based compound, characterized in that selected from the group consisting of transition metal, alkali metal, lanthanum metal, mercury (Hg). A precursor preparation step of preparing a polymer resin-imidazole compound catalyst precursor covalently linked by reacting a polymer resin including a halogen group at a terminal with an imidazole compound and replacing the halogen group with an imidazole compound; A method for producing a heterogeneous metal catalyst for synthesizing a furan-based compound comprising the step of preparing a metal catalyst of the formula (I) by coordinating a metal element using the polymer resin-imidazole compound as a ligand. <Formula I>

In formula (I), R is an alkyl group or mesityl group with or without a hetero atom, and M is a metal element. 5. The method of claim 4, The polymer resin is a chloromethyl polystyrene resin, the halogen group is a method for producing a heterogeneous metal catalyst for synthesizing furan-based compound, characterized in that the chlorine group. 5. The method of claim 4, The metal element is a method for producing a heterogeneous metal catalyst for synthesizing a furan-based compound, characterized in that selected from the group consisting of transition metal, alkali metal, lanthanum metal, mercury (Hg). 5. The method of claim 4, The precursor preparation step, after the swelling of the polymer resin in an organic solvent, the addition of the imidazole compound, stirring, washing, and drying the preparation of the heterogeneous metal catalyst for synthesis of furan-based compound, characterized in that consisting of Way. 5. The method of claim 4, The catalyst preparing step includes swelling the polymer resin-imidazole compound in an organic solvent, and then adding a metal compound of any one of a metal halide, a sodium compound, a potassium compound, a lithium compound, and a magnesium compound in which the metal element is halogenated. After stirring, washing, and drying, the method for producing a heterogeneous metal catalyst for synthesizing a furan-based compound, characterized in that consisting of. 9. The method according to claim 7 or 8, The organic solvent is N-methylpyrrolidone (NMP), dimethyl sulfoxide (DMSO), dimethylformamide (DMF), tetrahydrofuran (THF), ether, dimethoxyethane, nitromethane, hexane, toluene, dichloro A method for producing a heterogeneous metal catalyst for synthesizing furan-based compounds, characterized in that at least one of methane, chloroform, dioxane, acetonitrile, water, ethanol and methanol.

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