JP6314516B2 - Method for producing organosilica mesoporous material - Google Patents

Description

  The present invention relates to a method for producing an organic silica mesoporous material, and more particularly to a method for producing an organic silica mesoporous material having a bipyridine group or a pyridine group.

  Conventionally, it has been studied to introduce organic groups having various functional groups into a silica mesoporous material in which mesopores are regularly arranged to improve the properties of the silica mesoporous material such as adsorption properties. For example, JP 2010-116512 A (Patent Document 1) discloses an organic silica mesoporous material in which a pyridine group or a bipyridine group is introduced into a silica mesoporous material. Also, Angew. Chem. Int. Ed. 2011, 50, 11667-11671 (Non-Patent Document 1) discloses an organic silica mesoporous material in which a phenylpyridine group is introduced into a silica mesoporous material.

  In Patent Document 1, an organic cross-linked silane compound in which two ethoxysilyl groups are cross-linked with a divinylpyridine group is used, and an organosilane mesoporous material having a divinylpyridine group is obtained by hydrolysis and condensation polymerization at room temperature. It has been disclosed that it has been synthesized. In Non-Patent Document 1, an organic cross-linked silane compound in which two ethoxysilyl groups are cross-linked with a phenyl pyridine group is used. It is disclosed that a porous body has been synthesized.

JP 2010-116512 A

M.M. Waki et al., Angew. Chem. Int. Ed. 2011, 50, 11667-11671.

  According to the synthesis methods described in Patent Documents 1 and 2, the present inventors can sufficiently perform hydrolysis / condensation reaction even if a pyridine-based organosilane compound having an isopropoxysilyl group is hydrolyzed / condensed at room temperature. I found that it did not progress. It has also been found that when the reaction temperature is increased, the bond between the pyridine group or bipyridine group and the silyl group is cleaved, and the desired organosilica mesoporous material is not synthesized.

  This invention is made | formed in view of the subject which the said prior art has, and provides the method of manufacturing a pyridine type organic silica mesoporous material using the pyridine type organic silane compound which has an isopropoxy silyl group as a raw material. Objective.

  As a result of intensive studies to achieve the above object, the present inventors have conducted a reaction temperature in the case of hydrolyzing and polycondensing an organosilane compound having a bipyridine group or a pyridine group and having an isopropoxysilyl group. Has been found to be relatively high and the base concentration needs to be low, and the present invention has been completed.

That is, the method for producing an organosilica mesoporous material of the present invention comprises a surfactant, a temperature of 30 to 80 ° C., and a base concentration [OH ⁻ ] of 0.01 to 0.5 mol / L. A pyridine group- containing organosilane compound represented by (1) and a pyridine group- containing organosilane compound represented by the following formula (2):

[At least one group among R ^{11 to} R ¹⁴ and at least one group among R ^{15 to} R ^{18 in} the formula (1), and among R ^{21 to} R ²⁵ in the formula (2) At least two groups of the following formula (3):
-Y- [Si (O-iPr) ₃ ] _k (3)
(In the formula (3), Y is a divalent or trivalent organic group selected from the group consisting of an alkylene group, an alkenylene group, an alkynylene group, and an arylene group, or a single bond, and k is 1 or 2. is there)
Wherein the remaining groups of R ^{11 to} R ¹⁸ and R ^{21 to} R ^{25 in} the formulas (1) and (2) are hydrogen atoms, X in (1) is either a nitrogen atom or a carbon atom]
An addition step of adding a pyridine-based organosilane compound having at least one isopropoxysilyl group selected from the group consisting of:
A reaction step of hydrolyzing and polycondensing the pyridine-based organosilane compound at a temperature of 30 to 80 ° C. to obtain an organosilica mesostructure containing the surfactant, and the surfactant from the organosilica mesostructure Removing the template to obtain an organosilica mesoporous material by removing,
It is characterized by including.

Moreover, in the addition process concerning this invention, the addition rate V (unit: mol / h) of all the organosilane compounds and the number of moles M (unit: mol) of the base in a solution are the following formula (a):
0.1 ≦ V / M ≦ 2 (a)
It is preferable to add the pyridine-based organosilane compound so as to satisfy the condition represented by:

  Furthermore, in the method for producing an organosilica mesoporous material of the present invention, it is preferable to subject the reaction mixture obtained in the addition step to ultrasonic treatment at a temperature of 30 to 80 ° C., and before the template removal step. Furthermore, it is preferable to subject the organic silica mesostructure to a hydrothermal treatment.

  According to the present invention, a pyridine-based organic silica mesoporous material can be produced using a pyridine-based organic silane compound having an isopropoxysilyl group as a raw material.

2 is a graph showing an X-ray diffraction pattern of a bipyridine group-containing organic silica mesoporous material obtained in Example 1. FIG. 2 is a graph showing a nitrogen adsorption isotherm of a bipyridine group-containing organic silica mesoporous material obtained in Example 1. FIG. 2 is a graph showing an X-ray diffraction pattern of a bipyridine group- and biphenyl group-containing organic silica mesoporous material obtained in Example 2. FIG. 4 is a graph showing a nitrogen adsorption isotherm of a bipyridine group- and biphenyl group-containing organic silica mesoporous material obtained in Example 2. 4 is a graph showing an X-ray diffraction pattern of a bipyridine group- and ethylene group-containing organic silica mesoporous material obtained in Example 3. FIG. It is a graph which shows the nitrogen adsorption isotherm of the bipyridine group and ethylene group containing organosilica mesoporous material obtained in Example 3. 2 is a photograph showing the colloid (reaction suspension) obtained in Comparative Example 1. 4 is a graph showing an IR absorption spectrum of the reaction suspension obtained in Comparative Example 1. 4 is a graph showing a ²⁹ Si-MAS NMR spectrum of the hydrolyzed / condensed polymer obtained in Comparative Example 2. FIG. 6 is a photograph showing the colloid (reaction suspension) obtained in Comparative Example 3. 6 is a graph showing an IR absorption spectrum of the reaction suspension obtained in Comparative Example 3.

  Hereinafter, the present invention will be described in detail with reference to preferred embodiments thereof.

(Pyridine-based organosilane compound)
First, the pyridine-based organosilane compound used in the present invention will be described. In the present invention, at least one isoform selected from the group consisting of an organosilane compound having a pyridine group represented by the following formula (1) and an organosilane compound having a pyridine group represented by the following formula (2). A pyridine-based organosilane compound having a propoxysilyl group (hereinafter referred to as “isopropoxysilyl group-containing pyridine-based organosilane compound”) is used.

In the formula (1), at least one group of R ^{11 to} R ¹⁴ and at least one group of R ^{15 to} R ¹⁸ are represented by the following formula (3):
-Y- [Si (O-iPr) ₃ ] _k (3)
The group which has the isopropoxy silyl group represented by these, and the remaining group is a hydrogen atom. In the formula (2), at least two groups out of R ^{21 to} R ²⁵ are groups having an isopropoxysilyl group represented by the formula (3), and the remaining groups are hydrogen atoms. . Furthermore, X in the formula (1) is either a nitrogen atom or a carbon atom.

  In the formula (3), Y is an alkylene group (preferably having 1 to 12 carbon atoms, more preferably 1 to 6 carbon atoms) or an alkenylene group (preferably having 2 to 12 carbon atoms, more preferably 2 to 6 carbon atoms). ), An alkynylene group (preferably having 2 to 12 carbon atoms, more preferably 2 to 6 carbon atoms), an arylene group (preferably having 6 to 12 carbon atoms), an ether group, a carbonyl group, an amino group, an amide group, and an imide group. A divalent or trivalent organic group selected from the group consisting of or a single bond, and k is 1 or 2. As Y in the formula (3), either an alkylene group or a single bond is preferable, and a single bond is more preferable.

  In the present invention, the isopropoxysilyl group-containing pyridine-based organosilane compound may be used alone or in combination with other organosilane compounds. The ratio of the isopropoxysilyl group-containing pyridine-based organosilane compound in the total organosilane compound used as a raw material is not particularly limited as long as it is 1% by mass or more (the ratio of other organosilane compounds is 99% by mass or less). However, in the obtained organic silica mesoporous material, the amount of bipyridine group or pyridine group is increased, and the function as a solid ligand of the metal complex is improved. The proportion is preferably 0 to 90 mass%), more preferably 30 to 100 mass% (the proportion of other organic silane compounds is 0 to 70 mass%), and 50 to 100 mass% (the proportion of other organic silane compounds is 0). To 50% by mass) is more preferable, and 70 to 100% by mass (the ratio of other organosilane compounds is 0 to 30% by mass) is particularly preferable. 0 wt% (percentage of 0% by mass of other organic silane compound) is most preferred.

  Examples of the other organic silane compounds include dialkoxysilanes such as dimethoxysilane, diethoxysilane, and diisopropoxysilane; trialkoxysilanes such as trimethoxysilane, triethoxysilane, and triisopropoxysilane; tetramethoxysilane, tetraethoxysilane, Tetraalkoxysilanes such as tetradiisopropoxysilane; 1,2-bis (triethoxysilyl) ethane, 1,2-bis (triethoxysilyl) ethylene, 1,2-bis (triethoxysilyl) acetylene, 1,4- Bis (triethoxysilyl) benzene, 4,4′-bis (triethoxysilyl) biphenyl, 1,2-bis (triisopropoxysilyl) ethane, 1,2-bis (triisopropoxysilyl) ethylene, 1,2 -Bis (triiso Ropokishishiriru) acetylene, 1,4-bis (triisopropoxysilyl) benzene, 4,4'-bis (known alkoxysilane compounds such as organic groups crosslinked alkoxysilane such triisopropoxysilyl) biphenyl. These alkoxysilane compounds may be used alone or in combination of two or more.

Among such other organosilane compounds, the following formula (4):
(R ³² O) ₃ Si—R ³¹ —Si (OR ³² ) ₃ (4)
An organic group-crosslinked alkoxysilane represented by the formula is preferred.

In the formula (4), R ³¹ is a divalent to tetravalent organic group, an alkylene group (preferably having 1 to 12 carbon atoms, more preferably 1 to 6 carbon atoms), an alkenylene group (preferably having 2 carbon atoms). -12, more preferably 2 to 6 carbon atoms), an alkynylene group (preferably 2 to 12 carbon atoms, more preferably 2 to 6 carbon atoms), an arylene group (preferably 6 to 12 carbon atoms), and the like. ^{Further, R 32} is (preferably 1 to 4) each independently a C1-8 alkyl group.

(Surfactant)
Next, the surfactant used in the present invention will be described. In the present invention, the surfactant functions as a template for forming a mesopore in the micelle or liquid crystal structure. Such a surfactant is not particularly limited and may be any of cationic, anionic and nonionic, specifically, alkyltrimethylammonium, alkyltriethylammonium, dialkyldimethylammonium, benzylammonium. Such as chlorides, bromides, iodides or hydroxides; fatty acid salts, alkyl sulfonates, alkyl phosphates, polyethylene oxide nonionic surfactants, primary alkyl amines and the like. These surfactants may be used alone or in combination of two or more.

Among the surfactants, examples of the polyethylene oxide nonionic surfactant include a polyethylene oxide nonionic surfactant having a hydrocarbon group as a hydrophobic component and polyethylene oxide as a hydrophilic portion. Such surfactants, for example, the general formula _{C n H 2n + 1 (OCH} 2 CH 2) expressed in m OH, n is 10 to 30, m can be preferably used those which are 1 to 30. Further, esters of fatty acids such as oleic acid, lauric acid, stearic acid and palmitic acid and sorbitan, or compounds obtained by adding polyethylene oxide to these esters can also be used as the polyethylene oxide nonionic surfactant.

Furthermore, a triblock copolymer type polyalkylene oxide can also be used as the polyethylene oxide nonionic surfactant. Examples of such surfactants include those composed of polyethylene oxide (EO) and polypropylene oxide (PO) and represented by the general formula (EO) _x (PO) _y (EO) _x . x and y represent the number of repetitions of EO and PO, respectively, x is preferably 5 to 110, y is preferably 15 to 70, x is preferably 13 to 106, and y is more preferably 29 to 70. Examples of the triblock copolymer include (EO) ₁₉ (PO) ₂₉ (EO) ₁₉ , (EO) ₁₃ (PO) ₇₀ (EO) ₁₃ , (EO) ₅ (PO) ₇₀ (EO) ₅ , (EO) _13. (PO) ₃₀ (EO) ₁₃ , (EO) ₂₀ (PO) ₃₀ (EO) ₂₀ , (EO) ₂₆ (PO) ₃₉ (EO) ₂₆ , (EO) ₁₇ (PO) ₅₆ (EO) ₁₇ , (EO ) ₁₇ (PO) ₅₈ (EO) ₁₇ , (EO) ₂₀ (PO) ₇₀ (EO) ₂₀ , (EO) ₈₀ (PO) ₃₀ (EO) ₈₀ , (EO) ₁₀₆ (PO) ₇₀ (EO) ₁₀₆ , (EO) ₁₀₀ (PO) ₃₉ (EO) ₁₀₀ , (EO) ₁₉ (PO) ₃₃ (EO) ₁₉ , (EO) ₂₆ (PO) ₃₆ (EO) ₂₆ may be mentioned. These triblock copolymers are available from BASF, Aldrich, etc., and triblock copolymers having desired x and y values can be obtained at a small scale production level.

Further, a star diblock copolymer in which two polyethylene oxide (EO) chains-polypropylene oxide (PO) chains are bonded to two nitrogen atoms of ethylenediamine can also be used as the polyethylene oxide nonionic surfactant. Examples of such star diblock copolymers include those represented by the general formula ((EO) _x (PO) _y ) ₂ NCH ₂ CH ₂ N ((PO) _y (EO) _x ) ₂ . Here, x and y represent the number of repetitions of EO and PO, respectively, x is preferably 5 to 110, y is preferably 15 to 70, x is 13 to 106, and y is 29 to 70. preferable.

Among such surfactants, a salt (preferably a halide salt) of alkyltrimethylammonium [C _p H _{2p + 1} N (CH ₃ ) ₃ ] from the viewpoint that a mesoporous organic silica having regular mesopores can be obtained. ) Is preferably used. In that case, the alkyl group in the alkyltrimethylammonium preferably has 8 to 22 carbon atoms. Examples thereof include octadecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, tetradecyltrimethylammonium chloride, dodecyltrimethylammonium bromide, decyltrimethylammonium bromide, octyltrimethylammonium bromide, docosyltrimethylammonium chloride, and the like.

(Other ingredients)
In the present invention, a basic substance is used to adjust the base concentration of the reaction solution to a predetermined value. Such basic substances include alkali metal and alkaline earth metal hydroxides such as sodium hydroxide, potassium hydroxide, magnesium hydroxide, calcium hydroxide, barium hydroxide, ammonium hydroxide (ammonia water), etc. Is mentioned.

<Method for producing organic silica mesoporous material>
(Preparation of surfactant-containing solution)
In the present invention, first, the surfactant and a solvent are mixed to prepare a solution containing the surfactant (hereinafter referred to as “surfactant-containing solution”). Examples of the solvent include water, a water-miscible organic solvent (for example, a lower alcohol (preferably having a carbon number of 6 or less), acetone, acetonitrile, tetrahydrofuran, 1,4-dioxane and the like) and water. . The concentration of the surfactant in this solution is preferably 0.1 to 10% by mass, and more preferably 0.5 to 5% by mass. When the concentration of the surfactant is less than the lower limit, pore formation tends to be incomplete, whereas when the upper limit is exceeded, the amount of surfactant remaining in the solution increases, Uniformity tends to decrease. Further, by using the surfactant-containing solution having the above-mentioned concentration, an organic silica mesostructure containing the surfactant in a proportion of 20 to 90% by mass (preferably 30 to 70% by mass) tends to be obtained. . When the content of the surfactant in the organosilica meso structure is less than the lower limit, the order of the mesopore structure tends to be lowered, and when the upper limit is exceeded, the uniformity of the mesopores is lowered. It tends to be easy.

Moreover, in this invention, when preparing the said surfactant containing solution, the said basic substance is added and base concentration [OH < ^- >] of the surfactant containing solution obtained is 0.01-0.5 mol / Adjust to L. When the base concentration is less than the lower limit, the hydrolysis / condensation polymerization reaction of the isopropoxysilyl group-containing pyridine-based organosilane compound does not proceed sufficiently, and it becomes difficult to obtain a desired organic silica mesoporous material. On the other hand, when the base concentration exceeds the upper limit, the hydrolysis / condensation reaction of the isopropoxysilyl group-containing pyridine-based organosilane compound proceeds, but in the resulting polycondensation product, a bipyridine group or a pyridine group and a silyl group. Since the bond between them is completely cleaved, it becomes difficult to obtain a desired organosilica mesoporous material. In addition, the hydrolysis / condensation reaction of isopropoxysilyl group-containing pyridine-based organosilane compound proceeds sufficiently, and the resulting polycondensation product has sufficient cleavage of the bipyridine group or the bond between the pyridine group and the silyl group. From the viewpoint of being suppressed, the base concentration [OH ⁻ ] is preferably 0.01 to 0.15 mol / L, and more preferably 0.015 to 0.1 mol / L.

(Addition process)
Next, the surfactant-containing solution prepared in this way is heated to a temperature of 30 to 80 ° C., and this isopropoxysilyl group-containing solution is added to the surfactant-containing solution while maintaining this temperature and stirring vigorously. A pyridine-based organic silane compound and other organic silane compounds are added as necessary (hereinafter, these are collectively referred to as “raw organic silane compounds”). When the temperature of the surfactant-containing solution is less than the lower limit, hydrolysis of the isopropoxysilyl group-containing pyridine-based organosilane compound does not proceed sufficiently, and a uniform reaction mixture (reaction suspension) cannot be obtained. On the other hand, when the temperature of the surfactant-containing solution exceeds the upper limit, the bond between the bipyridine group or the pyridine group and the silyl group is cleaved. Further, from the viewpoint that hydrolysis of the isopropoxysilyl group-containing pyridine-based organosilane compound proceeds sufficiently and the cleavage of the bond between the bipyridine group or the pyridine group and the silyl group is sufficiently suppressed, the surface activity The temperature of the agent-containing solution is preferably 40 to 70 ° C.

In this invention, it is preferable to add the said raw material organosilane compound in the state melt | dissolved in the solvent. Examples of the solvent include organic solvents miscible with water such as methanol, ethanol, n-propanol, iso-propanol, n-butanol, tetrahydrofuran, 1,4-dioxane, acetone and acetonitrile. As a density | concentration of the raw material organic silane compound in the solution to add, 0.5-10 mol / L is preferable. The addition of the solution containing the raw organic silane compound (hereinafter referred to as “raw organic silane compound-containing solution”) is preferably performed at the lowest possible speed. Specifically, the addition rate V (unit: mol / h) of all organosilane compounds in the raw material organosilane compound-containing solution and the number of moles M (unit: mol) of the base in the surfactant-containing solution are: Preferably, the following formula (a):
0.1 ≦ V / M ≦ 2 (a)
More preferably, the following formula (b):
0.2 ≦ V / M ≦ 1.5 (b)
It is more preferable to adjust the addition rate of the raw material organosilane compound-containing solution so as to satisfy the condition represented by: Thereby, it is possible to obtain an organic silica mesoporous material having more regular mesopores.

(Sonication process)
In the present invention, the reaction mixture (reaction suspension) obtained in the addition step is preferably subjected to ultrasonic treatment at a temperature of 30 to 80 ° C. (preferably 40 to 70 ° C.). Thereby, the particulate matter in the reaction mixture (reaction suspension) is uniformly dispersed, and an organic silica mesoporous material having more regular mesopores can be obtained. As other ultrasonic treatment conditions, oscillation frequency: 20 to 100 kHz, treatment time: 0.5 to 3 hours are preferable. When the sonication time is less than the lower limit, the effect of the sonication tends not to be sufficiently obtained. On the other hand, when the upper limit is exceeded, the effect of the sonication tends to be saturated.

(Reaction process)
Next, the reaction mixture (reaction suspension) obtained in the addition step or the ultrasonic treatment step is stirred at a temperature of 30 to 80 ° C. to hydrolyze / condensate the raw material organic silane compound. An organic silica mesostructure containing the surfactant is obtained. When the reaction temperature is lower than the lower limit, the hydrolysis / condensation polymerization reaction of the isopropoxysilyl group-containing pyridine-based organosilane compound does not proceed sufficiently, and it becomes difficult to obtain a desired organic silica mesoporous material. On the other hand, when the reaction temperature exceeds the upper limit, the hydrolysis / condensation reaction of the isopropoxysilyl group-containing pyridine-based organosilane compound proceeds, but the resulting polycondensation product has a bipyridine group or a pyridine group and a silyl group. Thus, it is difficult to obtain a desired organosilica mesoporous material. In addition, the hydrolysis / condensation reaction of isopropoxysilyl group-containing pyridine-based organosilane compound proceeds sufficiently, and the resulting polycondensation product has sufficient cleavage of the bipyridine group or the bond between the pyridine group and the silyl group. From the viewpoint of being suppressed, the reaction temperature is preferably 40 to 70 ° C.

  Moreover, as stirring time, 12 hours-3 days are preferable, and 1-2 days are more preferable. When the stirring time is less than the lower limit, the hydrolysis / condensation polymerization reaction of the isopropoxysilyl group-containing pyridine-based organosilane compound does not proceed sufficiently, and it tends to be difficult to obtain a desired organic silica mesoporous material. On the other hand, when the stirring time exceeds the upper limit, in the resulting polycondensation product, the bond between the pyridine group or bipyridine group and the silyl group starts to be cleaved, or the effect of stirring tends to be saturated.

  In the present invention, it is preferable that the suspension containing the organosilica mesostructure is allowed to stand while maintaining the reaction temperature. Thereby, it is possible to obtain an organic silica mesoporous material having more regular mesopores. The standing time is preferably 12 hours to 3 days, more preferably 1 to 2 days. If the standing time is less than the lower limit, the effect due to standing tends not to be sufficiently obtained. On the other hand, if the upper limit is exceeded, in the resulting polycondensation product, between the pyridine group or bipyridine group and the silyl group. There is a tendency for the bond of the metal to begin to break or the effect of standing still saturates.

  The suspension containing the organosilica mesostructure thus obtained is subjected to a solid-liquid separation treatment such as filtration to recover the organosilica mesostructure.

(Hydrothermal process)
In the present invention, the organic silica mesostructure is preferably subjected to hydrothermal treatment. Thereby, it is possible to obtain an organic silica mesoporous material having more regular mesopores. As a method of hydrothermal treatment, for example, the organic silica mesostructure is water or an aqueous solution containing a surfactant used when forming the organic silica mesostructure (the concentration of the surfactant is 0.1 to 10 mass) %, More preferably 0.5 to 5% by mass), and the resulting dispersion (pH 6 to 8) is allowed to stand at a temperature of 50 to 100 ° C. for 12 to 24 hours.

  The suspension containing the hydrothermally treated organic silica mesostructure thus obtained is subjected to solid-liquid separation treatment such as filtration to recover the organic silica mesostructure.

(Mold removal process)
Next, by removing the surfactant from the organosilica mesostructure obtained in the reaction step or hydrothermal treatment step, the portion where the surfactant was present in the organosilica mesostructure becomes mesopores. An organic silica mesoporous material is formed. As a method of removing the surfactant, for example, (i) a method of removing the surfactant by immersing the organic silica mesostructure in an organic solvent (for example, ethanol) having high solubility in the surfactant, (Ii) a method of removing the surfactant by baking the organosilica mesostructure at 250 to 550 ° C., (iii) immersing the organosilica mesostructure in an acidic solution (for example, dilute hydrochloric acid) and heating, An ion exchange method in which a surfactant is exchanged with hydrogen ions; (iv) the organic silica mesostructure is exposed to a heated acidic vapor (for example, hydrochloric acid vapor) and then immersed in an organic solvent (for example, ethanol) Examples include a method of eluting a surfactant in an organic solvent. The treatment conditions in these methods can be appropriately set depending on the type of surfactant, organic solvent, acidic vapor used and the like.

(Organic silica mesoporous material)
The organosilica mesoporous material thus obtained is at least one selected from the group consisting of a structure having a pyridine group represented by the following formula (5) and a structure having a pyridine group represented by the following formula (6). It is a pyridine-based organosilica mesoporous material having a seed structure.

In the formula (5), at least one group of R ^{51 to} R ⁵⁴ and at least one group of R ^{55 to} R ⁵⁸ are represented by the following formula (7):

And the remaining group is a hydrogen atom. In the formula (6), at least two of R ^{61 to} R ⁶⁵ are groups represented by the formula (7), and the remaining groups are hydrogen atoms. Furthermore, X in the formula (5) is either a nitrogen atom or a carbon atom.

  In the formula (7), Y represents an alkylene group (preferably having 1 to 12 carbon atoms, more preferably 1 to 6 carbon atoms), an alkenylene group (preferably having 2 to 12 carbon atoms, more preferably 2 to 6 carbon atoms). ), An alkynylene group (preferably having 2 to 12 carbon atoms, more preferably 2 to 6 carbon atoms), an arylene group (preferably having 6 to 12 carbon atoms), an ether group, a carbonyl group, an amino group, an amide group, and an imide group. A divalent or trivalent organic group selected from the group consisting of or a single bond, k is 1 or 2, and * is a binding site with an adjacent structure. As Y in Formula (7), either an alkylene group or a single bond is preferable, and a single bond is more preferable.

The pore diameter (center pore diameter) in the mesopore structure of such a pyridine-based organic silica mesoporous material is preferably 1 to 50 nm, and more preferably 2 to 30 nm. Moreover, as pore volume, 0.1 cm < ³ > / g or more is preferable and 0.3 cm < ³ > / g or more is more preferable. Furthermore, as a BET specific surface area, 100 cm < ² > / g or more is preferable and 300 cm < ² > / g or more is more preferable.

  The central pore diameter is a curve (pore diameter distribution curve) in which a value (dV / dD) obtained by differentiating the pore volume (V) with respect to the pore diameter (D) is plotted against the pore diameter (D). ) At the maximum peak, and can be determined by the method described below. That is, the sample is cooled to liquid nitrogen temperature (−196 ° C.), nitrogen gas is introduced, the adsorption amount is determined by a constant volume method or a gravimetric method, and then the pressure of the introduced nitrogen gas is gradually increased, Plot the adsorption amount of nitrogen gas against the equilibrium pressure to obtain the adsorption isotherm. Using this adsorption isotherm, a pore size distribution curve can be obtained by a calculation method such as Cranston-Inklay method, Pollimore-Heal method, BJH method or the like.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example.

Example 1
Octadecyltrimethylammonium chloride (C ₁₈ TMACl, 2.43 g, 6.98 mmol), distilled water (132 ml) and 6N aqueous sodium hydroxide solution (0.770 ml) were mixed, and the resulting aqueous surfactant solution (base concentration [OH ^- ]: 0.035 mol / L) was heated to 50 ° C. While maintaining the temperature at 50 ° C. and vigorously stirring using a magnetic stirrer (stirring speed: 1300 rpm), this surfactant aqueous solution was added to 5,5′-bis (triisopropoxysilyl) -2,2′-bipyridine. An ethanol solution (5 ml) of (Si-BPy-Si, 2.97 g, 5.26 mmol) was added dropwise using a syringe pump. The dropping rate of the ethanol solution is the ratio of the addition rate V of Si-BPy-Si (unit: mol / h) to the number of moles M of the base in the surfactant aqueous solution (unit: mol) (V / M) was adjusted in the range of 2.5 to 3.5 ml / h so that it would be 0.57 h- ¹ .

  The obtained reaction suspension was subjected to ultrasonic treatment (frequency: 40 kHz) for 2 hours or more at 50 ° C. using an ultrasonic device to uniformly disperse the particulate matter. Thereafter, the reaction suspension was stirred at 50 ° C. for 3 days (stirring speed: 500 rpm), and further allowed to stand at 50 ° C. for 3 days to obtain the following reaction formula (I):

The hydrolysis / condensation polymerization reaction represented by

The resulting precipitate was filtered using a pressure filtration device to obtain a bipyridine group-containing organic silica mesostructure containing a template surfactant (C ₁₈ TMACl) (yield: 2.39 g). This organosilica mesostructure was redispersed in a C ₁₈ TMACl aqueous solution (C ₁₈ TMACl (8.70 g) dissolved in distilled water (433 ml)). The obtained dispersion was allowed to stand at 95 ° C. for 24 hours to subject the organosilica mesostructure to hydrothermal treatment, and then the precipitate was collected by filtration using a pressure filtration device (yield: 1.56 g). The organosilica mesostructure after hydrothermal treatment is added to an acidic ethanol solution (ethanol (260 ml) added with 2N hydrochloric acid (7.2 ml)) and suspended overnight to remove the template surfactant. A light yellow to white powdery bipyridine group-containing organosilica mesoporous material (BPy-PMO) was obtained (yield: 1.39 g).

When the X-ray diffraction pattern of this organosilica mesoporous material BPy-PMO was measured using a powder X-ray diffractometer (“RINT-2200” manufactured by Rigaku Corporation), as shown in FIG. 1A, 2θ = 1.96. A diffraction peak derived from a regular hexagonal structure was observed at ° (d = 4.50 nm), 3.40 ° (d = 2.60 nm), and 3.84 ° (d = 2.30 nm). Further, diffraction derived from a layered arrangement structure of bipyridine groups at 2θ = 7.6 ° (d = 1.16 nm), 15.2 ° (d = 0.58 nm), and 23.0 ° (d = 0.39 nm). A peak was observed. Further, the nitrogen adsorption / desorption isotherm of the organosilica mesoporous material BPy-PMO was measured using an automatic specific surface area / pore distribution measuring device (“Autosorb-1 system” manufactured by Cantachrome) under conditions of liquid nitrogen temperature (−196 ° C.). As shown in FIG. 1B, it was confirmed that the organic silica mesoporous material BPy-PMO has regular mesopores. Further, when the specific surface area of this organosilica mesoporous material BPy-PMO was calculated by the BET method, it was 739 m ² / g, and when the center pore diameter was calculated by the DFT method, it was 38.0 mm, and the pore volume was It was 0.41 cm < ³ > / g when computed by the t-plot test.

(Example 2)
Octadecyltrimethylammonium chloride (C ₁₈ TMACl, 1.45 g, 4.17 mmol), distilled water (77.7 ml) and 6N aqueous sodium hydroxide solution (1.13 ml) were mixed, and the resulting aqueous surfactant solution (base concentration) [OH ⁻ ]: 0.09 mol / L) was heated to 50 ° C. While maintaining the temperature at 50 ° C. and vigorously stirring using a magnetic stirrer (stirring speed: 1300 rpm), this surfactant aqueous solution was added to 5,5′-bis (triisopropoxysilyl) -2,2′-bipyridine. An ethanol solution (3 ml) containing (Si-BPy-Si, 882 mg, 1.56 mmol) and 4,4'-bis (triisopropoxysilyl) biphenyl (Si-Bp-Si, 880 mg, 1.56 mmol) It was dripped using a syringe pump. The dropping rate of the ethanol solution includes the addition rate V of the Si-BPy-Si and Si-Bp-Si (unit: mol / h) and the number of moles M of the base in the surfactant aqueous solution (unit: mol) was adjusted in the range of 2.5 to 3.5 ml / h so that the ratio (V / M) to 0.31 h ⁻¹ was obtained.

  The obtained reaction suspension was subjected to ultrasonic treatment (frequency: 40 kHz) for 2 hours or more at 50 ° C. using an ultrasonic device to uniformly disperse the particulate matter. Thereafter, the reaction suspension was stirred at 50 ° C. for 3 days (stirring speed: 500 rpm), and further allowed to stand at 50 ° C. for 3 days to obtain the following reaction formula (II):

The hydrolysis / condensation polymerization reaction represented by

The resulting precipitate was collected using a pressure filtration device to obtain a bipyridine group-containing organic silica mesostructure containing a template surfactant (C ₁₈ TMACl) (yield: 900 mg). This organosilica mesostructure was redispersed in a C ₁₈ TMACl aqueous solution (C ₁₈ TMACl (3.17 g) dissolved in distilled water (162 ml)). The obtained dispersion was allowed to stand at 95 ° C. for 24 hours, and the organic silica mesostructure was subjected to hydrothermal treatment, and then the precipitate was collected by filtration using a pressure filtration device (yield: 800 mg). The organosilica mesostructure after hydrothermal treatment is added to an acidic ethanol solution (ethanol (150 ml) added with 2N hydrochloric acid (4.1 ml)) and suspended overnight to remove the template surfactant. A pale yellow to white powdery bipyridine group- and biphenyl group-containing organic silica mesoporous material (BPy-Bp-PMO) was obtained (yield: 649 mg).

When the X-ray diffraction pattern of this organosilica mesoporous material BPy-Bp-PMO was measured in the same manner as in Example 1, it was regular at 2θ = 2.02 ° (d = 4.37 nm) as shown in FIG. 2A. A diffraction peak derived from the mesostructure was observed. Further, diffraction derived from a layered arrangement structure of organic groups at 2θ = 7.56 ° (d = 1.17 nm), 15.1 ° (d = 0.59 nm), and 22.7 ° (d = 0.39 nm) A peak was observed. Furthermore, the nitrogen adsorption / desorption isotherm of the organosilica mesoporous material BPy-PMO was determined in the same manner as in Example 1. As a result, as shown in FIG. 2B, it was IV type, and the organosilica mesoporous material BPy-Bp-PMO was It was confirmed to have regular mesopores. Moreover, when the specific surface area of this organosilica mesoporous material BPy-Bp-PMO was calculated by the BET method, it was 960 m ² / g, and when the center pore diameter was calculated by the DFT method, it was 35.4 mm. It was 0.50 cm < ³ > / g when the capacity | capacitance was computed by t-plot test.

(Example 3)
Octadecyltrimethylammonium chloride (C ₁₈ TMACl, 1.01 g, 2.90 mmol), distilled water (134 ml) and 6N aqueous sodium hydroxide solution (2.02 ml) were mixed, and the resulting aqueous surfactant solution (base concentration [OH ^- ]: 0.09 mol / L) was heated to 50 ° C. While maintaining the temperature at 50 ° C. and vigorously stirring using a magnetic stirrer (stirring speed: 1300 rpm), this surfactant aqueous solution was added to 5,5′-bis (triisopropoxysilyl) -2,2′-bipyridine. An ethanol solution (1.27 ml) containing (Si-BPy-Si, 760 mg, 1.34 mmol) and 1,2-bis (triisopropoxysilyl) ethane (Si-Et-Si, 2.79, 6.35 mmol). ) Was added dropwise using a syringe pump. The dropping rate of the ethanol solution includes the addition rate V of the Si-BPy-Si and Si-Et-Si (unit: mol / h) and the number of moles M of the base in the surfactant aqueous solution (unit: mol) was adjusted in the range of 2.5 to 3.5 ml / h so that the ratio (V / M) to 0.32 h ⁻¹ was obtained.

  The obtained reaction suspension was subjected to ultrasonic treatment (frequency: 40 kHz) for 2 hours or more at 50 ° C. using an ultrasonic device to uniformly disperse the particulate matter. Thereafter, the reaction suspension was stirred at 50 ° C. for 3 days (stirring speed: 500 rpm), and further allowed to stand at 50 ° C. for 3 days to obtain the following reaction formula (III):

The hydrolysis / condensation polymerization reaction represented by

The resulting precipitate was collected using a pressure filtration device to obtain a bipyridine group-containing organic silica mesostructure containing a template surfactant (C ₁₈ TMACl) (yield: 1.73 g). This organosilica mesostructure was redispersed in a C ₁₈ TMACl aqueous solution (C ₁₈ TMACl (2.16 g) dissolved in distilled water (229 ml)). The obtained dispersion was allowed to stand at 95 ° C. for 24 hours to subject the organosilica mesostructure to hydrothermal treatment, and then the precipitate was collected by filtration using a pressure filtration device (yield: 1.34 g). The organosilica mesostructure after hydrothermal treatment is added to an acidic ethanol solution (ethanol (223 ml) added with 2N hydrochloric acid (6.2 ml)) and suspended overnight to remove the template surfactant. A light yellow to white powdery bipyridine group and ethylene group-containing organic silica mesoporous material (BPy-Et-PMO) was obtained (yield: 951 mg).

The X-ray diffraction pattern of this organosilica mesoporous material BPy-Et-PMO was measured in the same manner as in Example 1. As shown in FIG. 3A, it was regular at 2θ = 1.68 ° (d = 5.25 nm) A diffraction peak derived from the mesostructure was observed. On the other hand, no diffraction peak derived from the layered arrangement structure of organic groups was observed, suggesting that the pore walls have an amorphous structure. Furthermore, the nitrogen adsorption / desorption isotherm of the organosilica mesoporous material BPy-Et-PMO was determined in the same manner as in Example 1. As a result, as shown in FIG. 3B, it was IV type, and the organosilica mesoporous material BPy-Et- PMO was confirmed to have regular mesopores. Moreover, when the specific surface area of this organosilica mesoporous material BPy-Et-PMO was calculated by the BET method, it was 909 m ² / g, and when the center pore diameter was calculated by the DFT method, it was 44.0 mm. It was 0.47 cm < ³ > / g when the capacity | capacitance was computed by t-plot test.

(Comparative Example 1)
The ethanol solution of Si-BPy-Si was dropped into the surfactant aqueous solution in the same manner as in Example 1 except that the temperature was changed to room temperature (25 ° C.). As shown in FIG. 4A, unreacted Si -BPy-Si adhered to the reaction vessel and the stirring bar, and a uniform reaction suspension was not obtained. When the IR absorption spectrum of this reaction suspension was measured, as shown in FIG. 4B, a peak derived from an isopropoxysilyl group was observed at a wave number of 2993 cm ⁻¹ and the hydrolysis reaction did not proceed at room temperature (25 ° C.). I understood it.

(Comparative Example 2)
A hydrolysis / condensation polymerization reaction was performed in the same manner as in Example 1 except that the temperature was changed to 95 ° C. When the reaction product was analyzed by ²⁹ Si-MAS NMR, as shown in FIG. 5, a peak derived from the Q site was observed at a chemical shift of −90 to −120 ppm, and at a reaction temperature of 95 ° C., the bipyridine group and silyl group were observed. It was found that the bond between the groups was completely cleaved.

(Comparative Example 3)
The surfactant aqueous solution was added to the surfactant aqueous solution in the same manner as in Example 1 except that the base concentration [OH ⁻ ] of the surfactant aqueous solution was changed to 0.005 mol / L by changing the amount of 6N sodium hydroxide aqueous solution added. Although an ethanol solution of BPy-Si was added dropwise, as shown in FIG. 6A, unreacted Si-BPy-Si adhered to the reaction vessel and the stirrer, and a uniform reaction suspension was not obtained. When the IR absorption spectrum of this reaction suspension was measured, as shown in FIG. 6B, a peak derived from an isopropoxysilyl group was observed at a wave number of 2973 cm ⁻¹ , and the base concentration [OH ⁻ ] was 0.005 mol / L. It was found that the hydrolysis reaction did not proceed under the above conditions.

(Comparative Example 4)
The hydrolysis / condensation polymerization reaction was carried out in the same manner as in Example 1 except that the amount of the 6N sodium hydroxide aqueous solution was changed to change the base concentration [OH ⁻ ] of the surfactant aqueous solution to 0.6 mol / L. . When the reaction product was analyzed by ²⁹ Si-MAS NMR, a peak derived from the Q site was observed at a chemical shift of −90 to −120 ppm, and the base concentration [OH ⁻ ] was 0.6 mol / L. It was found that the bond between the silyl group and the silyl group was completely cleaved.

  As described above, according to the present invention, a pyridine-based organic silica mesoporous material can be produced using a pyridine-based organic silane compound having an isopropoxysilyl group as a raw material.

  In such a pyridine-based organic silica mesoporous material, bipyridine groups and pyridine groups are exposed on the surface of the mesopores, so that metal ions are easily coordinated, and the pyridine-based organic silica mesoporous material obtained by the present invention is a metal Useful as a solid ligand of the complex.

Claims (4)

A pyridine group- containing organosilane compound represented by the following formula (1) and a solution containing a surfactant, having a temperature of 30 to 80 ° C. and a base concentration [OH ⁻ ] of 0.01 to 0.5 mol / L, and Pyridine group-containing organosilane compound represented by the following formula (2):
[At least one group among R ^{11 to} R ¹⁴ and at least one group among R ^{15 to} R ^{18 in} the formula (1), and among R ^{21 to} R ²⁵ in the formula (2) At least two groups of the following formula (3):
-Y- [Si (O-iPr) ₃ ] _k (3)
(In the formula (3), Y is a divalent or trivalent organic group selected from the group consisting of an alkylene group, an alkenylene group, an alkynylene group, and an arylene group, or a single bond, and k is 1 or 2. is there)
Wherein the remaining groups of R ^{11 to} R ¹⁸ and R ^{21 to} R ^{25 in} the formulas (1) and (2) are hydrogen atoms, X in (1) is either a nitrogen atom or a carbon atom]
An addition step of adding a pyridine-based organosilane compound having at least one isopropoxysilyl group selected from the group consisting of:
A reaction step of hydrolyzing and polycondensing the pyridine-based organosilane compound at a temperature of 30 to 80 ° C. to obtain an organosilica mesostructure containing the surfactant, and the surfactant from the organosilica mesostructure Removing the template to obtain an organosilica mesoporous material by removing,
A process for producing an organosilica mesoporous material, comprising: In the addition step, the addition rate V (unit: mol / h) of all organosilane compounds and the number of moles M (unit: mol) of the base in the solution are represented by the following formula (a):
0.1 ≦ V / M ≦ 2 (a)
The method for producing an organosilica mesoporous material according to claim 1, wherein the pyridine-based organosilane compound is added so as to satisfy a condition represented by:   The method for producing an organic silica mesoporous material according to claim 1 or 2, wherein the reaction mixture obtained in the adding step is subjected to ultrasonic treatment at a temperature of 30 to 80 ° C.   The method for producing an organic silica mesoporous material according to any one of claims 1 to 3, wherein the organosilica mesostructure is subjected to a hydrothermal treatment before the template removing step.