Stable multi-component porous organic molecular cage, preparation method and application thereof

Abstract

The invention relates to a multi-component organic molecular cage compound, which has C = N, B-N and B-O bonds formed through a bonding reaction, and has a connecting structure as shown in the following formula I: # imgabs0 which is assembled by three types of synthons of tetraaldehyde calix [4] resorcinol aromatic hydrocarbon, amino-substituted phenylboronic acid and alcohol. The multi-component organic molecular cage can change the type of alcohol through simple post-exchange to realize the change of optical properties and the like of the material, so that the application of the material in different fields is realized. The multi-component organic molecular cage material is simple in preparation process, low in cost, easy and convenient to operate and high in yield, and the prepared product is high in chemical stability, large in specific surface area and good in repeatability and has very high operability and practicability.

Description

Technical Field

[0001] The present invention belongs to the field of synthesis of porous materials, and specifically relates to a class of stable multi-component porous organic molecular cages, a preparation method thereof, and an application thereof. Background Art

[0002] In nature, functional biological encapsulants with complexity and diversity are usually assembled from sub-components of multiple different species through a multi-component self-assembly process. To mimic the self-assembly behavior in natural systems, synthetic chemists have prepared artificial molecular structures from simple fragments through self-assembly strategies, such as macrocyclic compounds and cage structures with different topologies, shapes, and functions. Although significant success has been achieved in the research in this field, the ability to assemble discrete molecular entities with molecular specificity from multiple synthetic units (>50) in a reproducible manner through self-assembly still faces great challenges in the supramolecular field. In addition, most of the assembled bodies are assembled from only one or two types of organic synthons, thus strongly limiting their structural diversity and functions.

[0003] Molecular cages (also known as molecular containers and molecular capsules) can be classified into porous organic cages (POCs), metal-organic cages (MOCs), hydrogen-bonded cages, and anion coordination cages, etc., according to the connection methods used for their synthesis. Among them, POCs are constructed from pure organic compounds through covalent self-assembly into discrete macromolecules, having inherent permanent cavities, and showing many promising applications, such as stabilization of active species, selective host inclusion and separation, and supramolecular catalysis. However, so far, most POCs are assembled from two types of organic synthons, specifically including [1+1], [2+4], [2+5], [3+6], [4+6], [4+8], [6+12], [8+12], [12+24] topologies, while the use of more than two different types of organic synthons to prepare multi-component organic molecular cages with more functional properties is still in its infancy. Currently, only a few reports have constructed multi-component porous organic cages MPOCs with a small number of components. For example, POCs with [1+3+3], [1+2+6], [2+3+6], [2+4+8], [3+6+6] assembly methods can be found in three-component POCs, which is probably because it is difficult to design and synthesize these specific multi-component assemblies. Therefore, it is extremely necessary to develop a simple method for constructing stable multi-component organic molecular cages with more functional properties and a preparation method thereof. Summary of the Invention

[0004] The present invention provides a novel multi-component organic molecular cage prepared by a simple one-step self-assembly method, which simultaneously contains C=N, B-N, and B-O bonds and has a stable coronavirus-shaped structure.

[0005] To achieve the above-mentioned invention object, the present invention provides the following technical solutions:

[0006] A multi-component organic molecular cage compound (abbreviated as MPOC), which has C=N, B-N, and B-O bonds formed by a bonding reaction, and has a connecting structure as shown in Formula I below:

[0007]

[0008] Wherein, Y is selected from alkyl; aryl; halogen, hydroxyl and / or aryl-substituted alkyl. Preferably, the alkyl is selected from C 1-6 alkyl, the aryl is selected from phenyl or naphthyl, where represents the bond connecting the connecting structure of Formula I to other groups in the organic molecular cage compound. As an example, Y is selected from the following structures:

[0009] -CH3, -C2H5, -C3H7, HOCH2CH2CH2-, CF3CH2-, CH3(CH3CH2)CH-,

[0010] where * represents the position where Y is bonded to O in Formula I.

[0011] According to an embodiment of the present invention, the MPOC compound is assembled from three types of synthons: tetraaldehyde calix[4]resorcinarene, amino-substituted phenylboronic acid, and alcohol (YOH). Specifically, the amino group in the amino-substituted phenylboronic acid forms a C=N bond with the aldehyde group in the para position of the tetraaldehyde calix[4]resorcinarene through a Schiff base reaction, the boronic hydroxyl group in the amino-substituted phenylboronic acid forms B-O-Y with the hydroxyl group of the alcohol, and the amino group in the amino-substituted phenylboronic acid forms a B-N bond with its boron atom.

[0012] Preferably, the tetraaldehyde calix[4]resorcinarene is a synthon with an "inwardly concave" configuration and an alkyl group at the lower edge. In the present invention, the inwardly concave configuration means that the aldehyde groups of the synthon tetraaldehyde calix[4]resorcinarene face the same side. The inwardly concave configuration of the ligand is beneficial to the formation of the organic molecular cage of the present invention, which can be prepared by methods known in the prior art or purchased. As an example, the tetraaldehyde calix[4]resorcinarene is selected from the synthons shown in the following Formula II:

[0013]

[0014] In Formula II, R is selected from alkyl, preferably C 1-10 alkyl, C 1-6 alkyl, for example, R is methyl, Me; ethyl, Et; propyl, Pr; isobutyl, iBu.

[0015] The amino-substituted phenylboronic acid includes two configurations: linear and "V" type. As an example, it is selected from the synthons shown in the following formula III:

[0016]

[0017] In formula III, n is an integer from 1 to 6, preferably from 1 to 4, and R is selected from amino, amino-substituted alkyl, amino-substituted aryl, aminoalkyl-substituted aryl, preferably NH2, NH2-C 1-6 alkyl, phenyl substituted with NH2, NH2-C 1-6 alkyl-substituted phenyl. Specifically, the formula III is selected from the synthons of the following formula III':

[0018] wherein n is an integer from 1 to 4.

[0019] The alcohol is selected from aromatic alcohols and aliphatic alcohols, and the alcohol can be a racemate, a stereoisomer or an optical isomer. Preferably, the aliphatic alcohol is selected from C 1-6 alkyl monohydric alcohol, C 1-6 alkyl diol, and the C 1-6 alkyl is optionally substituted by halogen; the aromatic alcohol is selected from benzene or naphthalene substituted by C 1-6 alkyl monohydric alcohol or C 1-6 alkyl diol. As an example, the alcohol is selected from the synthons of the following formula IV:

[0020]

[0021] Those skilled in the art can understand that the alcohol is not limited to the alcohols defined above. According to the principle of forming the B-O-Y structure in the present invention, it can be predicted that all alcohols can be bonded to the boronic acid hydroxyl group.

[0022] In the embodiment (1) MPOC-1 of the present invention, the formula II is isobutyl-tetraaldehyde calix[4]resorcinarene (iBu-CR4ACHO), the formula III is 3-aminophenylboronic acid, and the formula IV is methanol; in an embodiment (2) MPOC-2 of the present invention, the formula II is isobutyl-tetraaldehyde calix[4]resorcinarene (iBu-CR4ACHO), the formula III is 4-aminophenylboronic acid, and the formula IV is methanol. In an embodiment (3) MPOC-2-EgO of the present invention, the formula II is isobutyl-tetraaldehyde calix[4]resorcinarene (iBu-CR4ACHO), the formula III is 4-aminophenylboronic acid, and the formula IV is ethylene glycol.

[0023] According to an embodiment of the present invention, the molar ratio of the amounts of the three synthons, namely tetraformylcalix[4]resorcinarene, amino-substituted phenylboronic acid, and alcohol, is 1:(3 to 6):(3 to 60), for example, 1:4:24, 1:5:36, 1:6:60. The amount of alcohol includes the reaction amount and the solvent amount.

[0024] According to the above embodiment (1) of the present invention, the multicomponent organic molecular cage compound (MPOC-1) is composed of 2 iBu-CR4ACHO, 8 3-aminophenylboronic acids, and 8 methanol, and its molecular formula is (C 152 H 160 B8N8O 24 ). Specifically, the porous organic cage compound has 2 concave iBu-CR4ACHO as vertices, and 4 3-aminophenylboronic acids each connected end to end (i.e., the amino group of the first molecule is connected to the boron in the second molecule) as columns, assembling into a lantern-shaped organic cage structure, where 8 methanol are connected to the boron and face the outside of the molecular cage. It contains 1 lantern-shaped cavity and 8 quadrilateral windows, and its molecular structure schematic diagram is shown in the following formula V:

[0025]

[0026] According to the above embodiment (2) of the present invention, the multicomponent organic molecular cage compound (MPOC-2) is composed of 6 iBu-CR4ACHO, 24 4-aminophenylboronic acids, and 24 methanol, and its molecular formula is (C 456 H 480 N 24 O 72 B 24 ). Specifically, the porous organic cage compound has 6 concave iBu-CR4ACHO as vertices, and 8 pairs of triangular macrocycles formed by connecting 3 4-aminophenylboronic acids connected end to end as faces, assembling into an octahedron-shaped organic cage structure, where 24 methanol are connected to the boron and face the outside of the molecular cage. It contains 1 octahedron-shaped cavity, 8 triangular windows, and 12 rhombus windows, and its molecular structure schematic diagram is shown in the following formula VI:

[0027]

[0028] According to the above embodiment (3) of the present invention, the multicomponent organic molecular cage compound (MPOC-2-EgO) is composed of 6 iBu-CR4ACHO, 24 4-aminophenylboronic acids, and 24 ethylene glycol, and its molecular formula is (C 480 H 504 N 24 O 96 B 24) Specifically, the porous organic cage compound is an octahedral organic cage assembled from 6 concave iBu-CR4ACHO as vertices, 8 triangular macrocycles formed by connecting 3 4-aminophenylboronic acids end to end as faces, and 24 ethylene glycols connected to boron and facing the outside of the molecular cage.

[0029] The present invention also provides an organic molecular cage crystal formed from the above multi-component organic molecular cage compound.

[0030] According to an embodiment of the present invention, two MPOC crystals of the present invention are formed from the multi-component organic molecular cage compound as described in the above formula V or VI diagram.

[0031] According to an embodiment of the present invention, the multi-component organic molecular cage MPOC-1 crystal has a space group of P21 / c and cell parameters of α = γ = 90°, β = 104.512, The multi-component organic molecular cage MPOC-2 crystal has a space group of R3 and cell parameters of α = β = 90°, γ = 120°,

[0032] According to an embodiment of the present invention, the multi-component organic molecular cage crystal is an ordered packing of the MPOC-1 and MPOC-2 organic cages described above in the present invention.

[0033] According to an embodiment of the present invention, the maximum cavity height and the maximum sphere diameter that can be accommodated in the multi-component organic molecular cage MPOC-1 crystal are approximately 1.17 nm and 0.72 nm; the maximum cavity height and the maximum sphere diameter that can be accommodated in the MPOC-2 crystal are approximately 2.35 nm and 1.51 nm.

[0034] According to an embodiment of the present invention, the number of porous organic cage molecules Z in the unit cell of the porous organic cage MPOC-1 crystal is 4; the number of porous organic cage molecules Z in the unit cell of the MPOC-2 crystal is 3.

[0035] According to an embodiment of the present invention, the average length of the window of the multi-component organic molecular cage MPOC-1 crystal is approximately 0.6 nm and the width is approximately 0.5 nm (it can pass molecules with a diameter of approximately 0.25 nm); the average length of the triangular window of the MPOC-2 crystal is approximately 0.6 nm (it can pass molecules with a diameter of approximately 0.3 nm), and the average length of the quadrilateral window is approximately 1 nm and the width is approximately 0.5 nm (it can pass molecules with a diameter of approximately 0.25 nm).

[0036] According to an embodiment of the present invention, the multi-component organic molecular cages MPOC-1 and MPOC-2 have respectively asFigure 1 and Figure 10 the crystal structure shown

[0037] According to an embodiment of the present invention, the multi-component organic molecular cages MPOC-1 and MPOC-2 crystals have the X-ray powder diffraction patterns as shown in Figure 6 and Figure 15 the X-ray powder diffraction pattern shown

[0038] According to an embodiment of the present invention, the BET surface area of the multi-component organic molecular cage MPOC-1 crystal is 150-600 m 2 g -1 , and an exemplary MPOC-1 is 346 m 2 g -1 . The BET surface area of the multi-component organic molecular cage MPOC-2 crystal is 400-1000 m 2 g -1 , and an exemplary MPOC-2 is 578 m 2 g -1 .

[0039] The present invention also provides a porous material formed from the above multi-component organic molecular cage compound

[0040] The present invention also provides a preparation method of the multi-component organic molecular cage, which includes the following steps: reacting three types of synthons, namely tetraformylcalix[4]resorcinarene, amino-substituted phenylboronic acid, and alcohol, under solvothermal conditions to obtain the molecular cage

[0041] According to an embodiment of the present invention, it optionally includes the following step: synthesizing other multi-component organic molecular cages from the molecular cage obtained above by an exchange strategy. That is, mixing the organic molecular cage prepared above with other alcohols and reacting under solvothermal conditions to obtain an organic molecular cage with this alcohol

[0042] According to an embodiment of the present invention, the synthons are as defined above. Exemplarily, the compound MPOC-1 is obtained by reacting iBu-CR4ACHO, 3-aminophenylboronic acid, and methanol; Exemplarily, the compound MPOC-2 is obtained by reacting iBu-CR4ACHO, 4-aminophenylboronic acid, and methanol

[0043] According to an embodiment of the present invention, the molar ratio of the amounts of iBu-CR4ACHO, amino-substituted phenylboronic acid, and alcohol synthons used as the synthons is 1∶(3-6)∶(3-60), and an exemplary ratio is 1∶4∶24

[0044] According to an embodiment of the present invention, the temperature of the reaction is 60-100 °C, such as 80 °C, 100 °C; the reaction time is 12-48 h, such as 24 h

[0045] According to an embodiment of the present invention, the reaction is carried out in an organic solvent. For example, the organic solvent can be N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMA), N-methylpyrrolidone (NMP), and preferably DMF.

[0046] According to an embodiment of the present invention, the preparation method further includes ultrasonic treatment of the reaction mixture before heating the reaction. Preferably, the ultrasonic treatment time can be 3 to 15 minutes. Exemplarily, it is about 5 minutes.

[0047] According to an embodiment of the present invention, the preparation method further includes: the process of collecting the organic molecular cage MPOC compound from the reaction solution after the reaction ends. The specific process is: at room temperature (10 - 30 °C), the solvent is filtered off, and exchanged with a low-polarity solvent (such as n-pentane, n-hexane, petroleum ether) for 2 - 4 days, and the fresh solvent is changed 2 - 4 times every day.

[0048] Beneficial effects:

[0049] As a new type of porous material, organic molecular cages have broad application prospects in the fields of separation, catalysis, energy, membrane materials, 3D printing, porous liquids, etc. due to their unique solubility, porosity, and processability. However, currently, most porous organic cages are formed by the condensation connection of two types of synthons through reversible imine bonds (C=N) or borate esters (B-O). On the one hand, this type of porous organic molecular cage is prone to hydrolysis, resulting in structural collapse, which greatly limits their applications in actual production and life; on the other hand, the two types of synthons also limit the structural and functional diversity of porous organic molecular cage materials. Therefore, it is very necessary to develop a simple method for constructing stable multi-component organic molecular cages with more functional properties and the resulting molecular cages to expand the practical applications of porous organic cages in various fields.

[0050] Specifically: The present invention provides a novel multi-component organic molecular cage with a coronavirus-shaped structure that is stable and simultaneously contains Schiff base reactions, i.e., C=N bonds, B-N bonds, and B-O bonds, prepared by a simple one-step self-assembly method from three types of synthons: tetraaldehyde calix[4]resorcinarene, amino-substituted phenylboronic acid, and alcohol. The preparation method of the present invention does not require a catalyst, the preparation process is simple, the operation is convenient, the yield is high, the prepared molecular cage has high chemical stability, a large specific surface area, and good repeatability. Therefore, this method has strong operability and practicality. In particular, different performance multi-component organic molecular cages can be prepared by introducing alcohols containing different substituent types through a simple "one-pot reaction" or post-modification synthesis method, so as to realize the application value of this type of organic molecular cage in different fields. Brief Description of the Drawings

[0051] Figure 1 Schematic diagram of the synthesis strategy and X-ray single crystal structure of the multi-component organic molecular cage MPOC-1.

[0052] Figure 2 1H NMR of MPOC-1 1 1H NMR

[0053] Figure 3 Comparison diagram of 1H NMR of MPOC-1 after soaking in water and the original 1H NMR 1 1H NMR

[0054] Figure 4 FT-IR spectrum of MPOC-1

[0055] Figure 5 TGA curve of MPOC-1

[0056] Figure 6 PXRD pattern of MPOC-1

[0057] Figure 7 77K N2 adsorption-desorption isotherm of MPOC-1

[0058] Figure 8 11B NMR of MPOC-1 11 11B NMR

[0059] Figure 9 13C NMR of MPOC-1 13 13C NMR

[0060] Figure 10 Schematic diagram of the synthesis strategy and X-ray single crystal structure of the multi-component organic molecular cage MPOC-2.

[0061] Figure 11 1H NMR of MPOC-2 1 1H NMR

[0062] Figure 12 Comparison diagram of 1H NMR of MPOC-2 after soaking in water and the original 1H NMR 1 1H NMR

[0063] Figure 13 FT-IR spectrum of MPOC-2

[0064] Figure 14 TGA curve of MPOC-2

[0065] Figure 15Powder X-ray diffraction (PXRD) pattern of MPOC-2.

[0066] Figure 16 77K N2 adsorption-desorption isotherm of MPOC-2.

[0067] Figure 17 11B NMR spectrum of MPOC-2 11

[0068] Figure 18 13C NMR spectrum of MPOC-2 13

[0069] Figure 19 1H NMR spectrum of MPOC-2-EgO 1

[0070] Figure 20 Synthesis strategy and X-ray single crystal structure of MPOC-2-EgO.

[0071] Figure 21 Fluorescence spectra of MPOC-2-NaMeO, MPOC-2-S-NaEtO and MPOC-2-R-NaEtO.

[0072] Figure 22 Circular dichroism (CD) spectra of MPOC-2-S-NaEtO and MPOC-2-R-NaEtO.

[0073] Figure 23 Synthesis strategy and structure of the multi-component organic molecular cage of the present invention. Detailed implementation mode

[0074] The technical solutions of the present invention will be further described in detail below with reference to specific embodiments. It should be understood that the following embodiments are only for illustrative and explanatory purposes of the present invention, and should not be construed as limiting the protection scope of the present invention. All technologies implemented based on the above content of the present invention are covered within the scope of protection intended by the present invention.

[0075] Unless otherwise specified, the raw materials and reagents used in the following examples are all commercially available products, or can be prepared by known methods.

[0076] Example 1

[0077] The preparation method of MPOC-1 includes the following steps:

[0078] ​​​(1) Synthesis of MPOC-1 crystal: 3-aminophenylboronic acid (10.95 mg, 0.08 mmol), C4RACHO (16.4 mg, 0.02 mmol), 1 mL of methanol and 3 mL of DMF were added to a 10 mL glass bottle and reacted at 100 °C for 24 h. A large amount of orange crystals were found to form on the bottle wall and bottom. The solvent was removed by filtration at room temperature, and the obtained crystals were exchanged with n-pentane for three days, with n-pentane being changed three times a day. The sample was activated under dynamic vacuum at 100 °C for 10 h. The yield of MPOC-1 was approximately 75%. 1H NMR (400 MHz, CDCl3): δ = 9.07 (s, 4H), 8.05 (s, 6H), 7.38 (s, 1H), 6.90 (s, 1H), 6.69 (s, 1H), 4.51 (s, 1H), 3.49 (s, 3H), 3.11 (m, 20H), 1.66 (t, 6H), 1.03 (d, 14H).

[0079] Characterization methods of MPOC-1:

[0080] (2) The structure of MPOC-1 characterized by single crystal X-ray diffraction (SCXRD) is shown in Table 1 below.

[0081] Table 1 shows the crystallographic data of MPOC-1

[0082]

[0083]

[0084] R1 a = ∑||F o |-|F c || / ∑|F o |. b wR2 = {∑[w(F o 2 -F c 2 ) 2 / ∑[w(F o 2 ) 2} 1 / 2

[0085] The single crystal structure in Table 1 shows that:

[0086] (3) The MPOC-1 crystal belongs to the monoclinic space group P21 / c and is composed of two iBu-CR4ACHO synthons as vertices and four 3-aminophenylboronic acids connected end to end as edges, and includes eight methanol molecules connected to boron and facing outward to assemble into an organic cage with a lantern-like structure. It contains one lantern-like cavity and eight windows. The maximum cavity height and the maximum diameter of the sphere that can be accommodated are approximately 1.17 nm and 0.72 nm, respectively. In addition, the window is approximately quadrilateral, with a length of about 0.6 nm and a width of about 0.5 nm for the quadrilateral window, and it can pass molecules with a diameter of about 0.25 nm (such as Figure 1 as shown).

[0087] (4) After soaking the MPOC-1 sample in water for 24 hours and then drying it again, a nuclear magnetic resonance hydrogen spectrum test was performed on the newly synthesized sample. The results are as Figure 3 shown. There is no change in the spectra of the two compared with before, verifying the stability of MPOC-1 in an aqueous environment.

[0088] (5) Figure 4 is the infrared spectrum (FT-IR) of MPOC-1. Through Fourier transform infrared spectroscopy (FT-IR) testing, characteristic infrared vibration signals of B-O (1310 cm -1 ), B-N (1465 cm -1 ), and C=C (1650 cm -1 ) in the MPOC-1 cage were observed, indicating the stable existence of MPOC-1 under solid state conditions.

[0089] (6) Figure 5 is the thermogravimetric curve (TGA) of MPOC-1. It can be seen from the TGA analysis chart that MPOC-1 can be stable up to 300 °C.

[0090] (7) Figure 6 is the X-ray powder diffraction (PXRD) pattern of MPOC-1, which has many sharp peaks in the range of 3-40°, indicating that the MPOC-1 sample is crystalline after activation.

[0091] (8) Figure 7 is the N2 adsorption-desorption curve of MPOC-1. According to the BET test, nitrogen adsorption at 77 K shows that the surface area of MPOC-1 is 346.41 m 2 g -1 .

[0092] (9) The dried MPOC-1 sample was characterized by nuclear magnetic resonance boron spectrum ( 11 11B NMR). The results are as Figure 8 shown. The appearance of the broad peak of B-N (4.64 ppm) in the figure represents the effective synthesis of the MPOC-1 organic cage.

[0093] (10) The dried MPOC-1 sample was characterized by carbon-13 nuclear magnetic resonance ( 13 13 C NMR), and the results are as Figure 9 shown. The appearance of many distinct characteristic peaks in the figure represents the successful synthesis of the MPOC-1 organic cage.

[0094] Example 2

[0095] The preparation method of MPOC-2 includes the following steps:

[0096] (1) Synthesis of MPOC-2 crystals: 4-aminophenylboronic acid (32.9 mg, 0.24 mmol), C4RACHO (49.2 mg, 0.06 mmol), 1 mL of methanol, and 4 mL of DMF were added to a 10 mL glass bottle and reacted at 100 °C for 12 h. A large amount of orange crystals were found to form on the bottle wall and bottom. The solvent was removed by filtration at room temperature, and the obtained crystals were exchanged with n-pentane for three days, with n-pentane being changed three times a day. The sample was activated under dynamic vacuum at 100 °C for 10 h, and the yield of MPOC-2 was approximately 71%. 1 1H NMR (400 MHz, CDCl3): δ = 8.62 (s, 4H), 7.63 (d, 6H), 6.95 (d, 1H), 6.48 (s, 1H), 6.19 (s, 1H), 4.65 (d, 2H), 3.24 (d, 6H), 2.09 (m, 10H), 1.45 (t, 2H), 1.05 (d, 14H).

[0097] Characterization methods of MPOC-2:

[0098] (2) The structure of MPOC-2 was characterized by single-crystal X-ray diffraction (SCXRD), and the results are shown in Table 2 below.

[0099] Table 2 shows the crystallographic data of MPOC-2

[0100]

[0101]

[0102] R1 a = ∑||F o |-|F c || / ∑|F o |. b wR2 = {∑[w(F o 2 - F c 2 ) 2 / ∑[w(F o 2 )2} 1 / 2

[0103] The single crystal structure in Table 2 shows that:

[0104] (3) MPOC-2 crystallizes in the trigonal system, space group R3, with 6 concave aromatic iBu-CR4ACHO as vertices, and 8 pairs of triangular macrocycles formed by connecting 3 4-aminophenylboronic acids end to end as faces, and 24 methanol molecules connected to boron and facing the outside of the molecular cage, assembling into an octahedral organic cage structure. The maximum cavity height and the diameter of the largest sphere that can be accommodated are approximately 2.35 nm and 1.51 nm, respectively. In addition, the cage contains two types of windows, where the average length of the triangular window is approximately 0.6 nm, which can pass molecules with a diameter of approximately 0.3 nm; the average length of the quadrilateral window is approximately 1 nm and the width is approximately 0.5 nm, which can pass molecules with a diameter of approximately 0.25 nm (as Figure 10 shown)

[0105] (4) The dried MPOC-2 sample was characterized by nuclear magnetic resonance hydrogen spectrum ( 1 1H NMR), and the results are as Figure 11 shown.

[0106] (5) After soaking the MPOC-2 sample in water for 24 hours and then drying it again, the nuclear magnetic resonance hydrogen spectrum test was carried out with the newly synthesized sample. The results are as Figure 12 shown, and there is no change in the spectra of the two compared with before, verifying the stability of MPOC-2 in the aqueous environment.

[0107] (6) Figure 13 is the infrared spectrum (FT-IR) of MPOC-2. Through Fourier transform infrared spectroscopy (FT-IR) test, the characteristic infrared vibration signals of B-O (1310 cm -1 -1), B-N (1465 cm -1 -1) and C=C (1650 cm -1 -1) in the MPOC-2 cage were observed, indicating that MPOC-2 exists stably under solid state conditions.

[0108] (7) Figure 14 is the thermogravimetric curve (TGA) of MPOC-2. It can be seen from the TGA analysis chart that MPOC-2 can be stable up to 300 °C.

[0109] (8) Figure 15 is the X-ray powder diffraction (PXRD) of MPOC-2. There are many sharp peaks in the range of 3-40°, indicating that the MPOC-2 sample is crystalline after activation.

[0110] (9) Figure 16N2 adsorption - desorption isotherm of MPOC - 2. Nitrogen adsorption at 77K shows that the surface area of MPOC - 2 is 578.65 m 2 g -1 .

[0111] (10) The dried MPOC - 2 sample was characterized by nuclear magnetic boron spectroscopy ( 11 11B NMR). The results are as Figure 17 shown. The appearance of the broad peak of B - N (4.70 ppm) in the figure represents the effective synthesis of the organic cage of MPOC - 2.

[0112] (11) The dried MPOC - 2 sample was characterized by nuclear magnetic carbon spectroscopy ( 13 13C NMR). The results are as Figure 18 shown. The appearance of many obvious characteristic peaks in the figure represents the effective synthesis of the organic cage of MPOC - 2.

[0113] Example 3

[0114] Preparation method of functionalized MPOC - 2 - EgO (ethylene glycol), comprising the following steps:

[0115] (1) Synthesis of MPOC - 2 - EgO crystals: Method A: Dissolve 76.8 mg of MPOC - 2 (0.01 mmol) in 4 mL of DMF in a 10 mL glass bottle, then add ethylene glycol (149 mg, 2.4 mmol) solution (dissolved in 1 ml of DCM), and sonicate for 5 min. The solution reacts at 100 °C for 24 h to obtain yellow blocky crystals. Then, filter to remove the solvent at room temperature, and exchange the crystals with n - pentane for three days, changing n - pentane three times a day. The sample is activated at 100 °C under dynamic vacuum for 10 h. The yield of MPOC - 2 - EgO is about 72%. Method B: Add 4 - aminophenylboronic acid (32.9 mg, 0.24 mmol), C4RACHO (49.2 mg, 0.06 mmol), 0.5 mL of ethylene glycol, and 4 ml of DMF into a 10 mL glass bottle, and react at 100 °C for 12 h. A large amount of orange - yellow crystals are found to form on the bottle wall and bottom. Then, filter to remove the solvent at room temperature, and exchange the crystals with n - pentane for three days, changing n - pentane three times a day. The sample is activated at 100 °C under dynamic vacuum for 10 h. The yield of MPOC - 2 - EgO is about 70%. 11H NMR (400 MHz, CDCl3): δ = 8.61 (s, 2H), 7.97 (s, 1H), 7.71 (d, 4H), 6.93 (d, 1H), 6.68 (s, 1H), 6.43 (s, 1H), 5.30 (s, 1H), 4.62 (t, 4H), 3.70 (s, 4H), 3.36 (s, 2H), 2.16 (s, 2H), 2.05 (t, 3H), 1.44 (d, 4H), 1.24 (m, 3H), 1.03 (d, 10H). Figure 19 For the characterization of the dried BPOC-2-EgO sample by nuclear magnetic resonance hydrogen spectrum 1 (1H NMR), characteristic peaks of ethylene glycol appear at 3.70 and 5.30 ppm in the figure, which proves that our post-modification strategy is feasible. In addition, we also successfully obtained the crystals of MPOC-2-EgO.

[0116] (3) The structure of MPOC-2-EgO characterized by single crystal X-ray diffraction (SCXRD) is shown in Table 3 below.

[0117] Table 3 shows the crystallographic data of MPOC-2-EgO

[0118]

[0119]

[0120] R1 a = ∑||F o |-|F c || / ∑|F o . b wR2 = {∑[w(F o 2 - F c 2 ) 2 / ∑[w(F o 2 ) 2} 1 / 2

[0121] The single crystal structure in Table 3 shows that:

[0122] (3) MPOC-2-EgO crystallizes in the monoclinic space group P23, with 6 concave iBu-CR4ACHO as vertices, and 8 pairs of triangular macrocycles formed by connecting 3 4-aminophenylboronic acids end to end as faces, and 24 ethylene glycols connected to boron and facing the outside of the molecular cage, assembled into an octahedral organic cage (as Figure 20 shown).

[0123] Example 4

[0124] Preparation method of functionalized MPOC-2-NaMeO (2-naphthylmethanol), comprising the following steps:

[0125] (1) Dissolve 76.8 mg of MPOC-2 (0.01 mmol) in 4 ml of DMF and place it in a 10 ml glass bottle. Then add a solution of 2-naphthylmethanol (380 mg, 2.4 mmol) (dissolved in 1 ml of DCM), and ultrasonicate for 5 min. React the solution at 100 °C for 24 h to obtain yellow block crystals. Then, filter to remove the solvent at room temperature, and exchange the crystals with n-pentane for three days, changing the n-pentane three times a day. Activate the sample under dynamic vacuum at 100 °C for 10 h. The yield of MPOC-2-NaMeO is about 68%.

[0126] (2) Perform fluorescence spectroscopy test on the sample MPOC-2-NaMeO at an excitation wavelength of 253 nm. We found that the sample showed obvious green under ultraviolet light, such as Figure 21 There is an obvious signal peak at an emission wavelength of 520 nm, indicating that our sample MPOC-2-NaMeO has good fluorescence properties. This phenomenon also shows that we have successfully modified 2-naphthylmethanol on the surface of MPOC-2.

[0127] Example 5

[0128] Preparation method of functionalized MPOC-2-S-NaEtO (S-1-naphthyl-1-ethanol), comprising the following steps:

[0129] (1) Dissolve 76.8 mg of MPOC-2 (0.01 mmol) in 4 ml of DMF in a 10 ml glass bottle. Then add a solution of S-1-naphthyl-1-ethanol (210 mg, 1.2 mmol) (dissolved in 1 ml of DCM), and ultrasonicate for 5 min. React the solution at 100 °C for 24 h to obtain yellow block crystals. Then, filter to remove the solvent at room temperature, and exchange the crystals with n-pentane for three days, changing the n-pentane three times a day. Activate the sample under dynamic vacuum at 100 °C for 10 h. The yield of MPOC-2-S-NaEtO is about 74%.

[0130] (2) In Figure 22 we can see that MPOC-2-S-NaEtO (S-1-naphthyl-1-ethanol) has strong CD signal peaks at 387(+), 404(+) and 449(-) nm, indicating that our sample has certain chiral properties. In addition, we also explored the fluorescence properties of MPOC-2-S-NaEtO. In Figure 22Among them, the fluorescence spectrum of the sample MPOC-2-S-NaEtO was tested at an excitation wavelength of 253 nm. We found that the sample showed obvious green under ultraviolet light and had an obvious signal peak at an emission wavelength of 520 nm. It can be seen that our sample MPOC-2-S-NaEtO has good fluorescence properties at the same time. Finally, through circularly polarized fluorescence test (CPL), we found that the dissymmetry factor glum value of the new Cage modified with S-1-naphthyl-1-ethanol was -5.47×10 -5 . At the same time, under the test with an excitation wavelength of 253 nm, we also saw an obvious excitation wavelength at 520 nm, which not only verified that the sample we obtained is a fluorescence performance material but also well illustrated that we successfully modified S-1-naphthyl-1-ethanol on the surface of MPOC-2.

[0131] Example 6

[0132] Preparation method of functionalized MPOC-2-R-NaEtO (R-1-naphthyl-1-ethanol), including the following steps:

[0133] (1) Dissolve 76.8 mg of MPOC-1 (0.01 mmol) in 4 ml of DMF in a 10 ml glass bottle, then add a solution of R-1-naphthyl-1-ethanol (210 mg, 1.2 mmol) (dissolved in 1 ml of DCM), and ultrasonicate for 5 min. The solution was reacted at 100 °C for 24 h to obtain yellow block crystals. Then, the solvent was removed by filtration at room temperature, and the crystals were exchanged with n-pentane for three days, changing n-pentane three times a day. The sample was activated at 100 °C under dynamic vacuum for 10 h. The yield of MPOC-2-R-NaEtO (R-1-naphthyl-1-ethanol) was about 74%.

[0134] (2) In Figure 22 we can see that MPOC-2-R-NaEtO has strong CD signal peaks at 387 (-), 404 (+) and 449 (+) nm, indicating that our sample has certain chiral properties. In addition, we also explored the fluorescence properties of MPOC-2-R-NaEtOH. In Figure 22 Among them, the fluorescence spectrum of the sample MPOC-2-R-NaEtOH was tested at an excitation wavelength of 253 nm. We found that the sample showed obvious green under ultraviolet light and had an obvious signal peak at an emission wavelength of 520 nm. It can be seen that our sample MPOC-2-R-NaEtO has good fluorescence properties at the same time. Finally, through circularly polarized fluorescence test (CPL), we found that the dissymmetry factor glum value of the new Cage modified with R-1-naphthyl-1-ethanol was 4.05×10 -5Meanwhile, under the test with an excitation wavelength of 253 nm, we also observed an obvious excitation wavelength at 520 nm, which not only verified that the obtained sample is a fluorescent material but also well demonstrated that we successfully modified R-1-naphthyl-1-ethanol on the surface of MPOC-2.

[0135] The above describes the embodiments of the present invention. However, the present invention is not limited to the above embodiments. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A multi-component organic molecular cage compound having C=N, B-N, and B-O bonds formed by a bonding reaction and having a connection structure as shown in Formula I below: Among them, Y is selected from alkyl; aryl; halogen, hydroxy and / or aryl-substituted alkyl. Preferably, the alkyl is selected from C 1-6 alkyl, the aryl is selected from phenyl or naphthyl, wherein represents a bond by which the linking structure shown in Formula I is bonded to other groups. As an example, the Y is selected from the following structures: -CH3, -C2H5, -C3H7, HOCH2CH2-, HOCH2CH2CH2-, CF3CH2-, CH3(CH3CH2)CH-, Wherein * represents the position where Y is linked to O in Formula I.

2. The multi-component organic molecular cage compound according to claim 1, which is assembled from three types of synthons: tetraaldehyde calix[4]resorcinarene, amino-substituted phenylboronic acid, and alcohol (YOH). Preferably, the tetraaldehyde calix[4]resorcinarene is selected from the synthons shown in Formula II below: In formula II, R is selected from alkyl groups, preferably C 1-10 alkyl groups, C 1-6 alkyl groups, for example, R is methyl, Me; ethyl, Et; propyl, Pr; isobutyl, iBu; The amino-substituted phenylboronic acid is selected from the synthons shown in Formula III below: In formula III, n is an integer from 1 to 6, preferably from 1 to 4, and R is selected from amino, amino-substituted alkyl, amino-substituted aryl, aminoalkyl-substituted aryl, preferably NH2, NH2-C1-6 alkyl, phenyl substituted with NH2, phenyl substituted with NH2-C 1-6 alkyl. Specifically, the formula III is selected from the synthons of the following formula III': where n is an integer from 1 to 4; The alcohol is selected from aromatic alcohols and aliphatic alcohols. Preferably, the aliphatic alcohol is selected from C 1-6 alkyl monohydric alcohols and C 1-6 alkyl dihydric alcohols, and the C 1-6 alkyl is optionally substituted by a halogen; the aromatic alcohol is selected from benzene or naphthalene substituted by a C 1-6 alkyl monohydric alcohol or a C 1-6 alkyl dihydric alcohol. As an example, the alcohol is selected from the synthons of the following formula IV:

3. The multi-component organic molecular cage compound according to claim 1, which is selected from the following specific molecular cage compounds: MPOC-1: It consists of 2 iBu-CR4ACHO, 8 3-aminophenylboronic acids and 8 methanol molecules, and its molecular formula is C 152 H 160 B8N8O 24 . The porous organic cage compound is a lantern-shaped organic cage assembled with 2 concave iBu-CR4ACHO as vertices and 4 columns each composed of 2 3-aminophenylboronic acids connected end to end. Among them, 8 methanol molecules are connected to boron and face the outside of the molecular cage; MPOC-2: It consists of 6 iBu-CR4ACHO, 24 4-aminophenylboronic acid, and 24 methanol, and its molecular formula is C 456 H 480 N 24 O 72 B 24 , and the porous organic cage compound is an octahedral organic cage assembled with 6 concave iBu-CR4ACHO as vertices and 8 pairs of triangular macrocycles formed by connecting 3 4-aminophenylboronic acids end to end as faces. Among them, 24 methanol are connected to boron and face the outside of the molecular cage; MPOC-2-EgO: It consists of 6 iBu-CR4ACHO, 24 4-aminophenylboronic acid, and 24 ethylene glycols, and its molecular formula is C 480 H 504 N 24 O 96 B 24 . The porous organic cage compound is an octahedral organic cage assembled with 6 concave iBu-CR4ACHO as vertices and 8 pairs of triangular macrocycles formed by connecting 3 4-aminophenylboronic acids end to end as faces. 24 ethylene glycols are connected to boron and face the outside of the molecular cage.

4. A crystal formed from the multi-component organic molecular cage compound according to any one of claims 1-3 Preferably, the crystal space group formed by the multi-component organic molecular cage MPOC-1 is P21 / c, and the unit cell parameters are α = γ = 90°, β = 101.807, The number of porous organic cage molecules Z in the unit cell is 4; Preferably, the crystal space group formed by the multi-component organic molecular cage MPOC-2 is R3, and the unit cell parameters are α = β = 90°, γ = 120°, The number of porous organic cage molecules Z in the unit cell is 3.

5. The crystal according to claim 4, wherein the crystal formed from the multi-component organic molecular cage MPOC-1 has an X-ray powder diffraction pattern as shown in Figure 6; the crystal formed from the multi-component organic molecular cage MPOC-2 has an X-ray powder diffraction pattern as shown in Figure 15.

6. A porous material formed from the multi-component organic molecular cage compound according to any one of claims 1-3, or formed from the organic molecular cage crystal according to any one of claims 4-5.

7. A method for preparing the multi-component organic molecular cage compound according to claim 1, which comprises the following steps: reacting three types of synthons, namely tetraaldehyde calix[4]resorcinarene, amino-substituted phenylboronic acid, and alcohol, under solvothermal conditions to obtain the molecular cage.

8. The preparation method according to claim 7, which optionally comprises the following steps: synthesizing other multi-component organic molecular cages from the above-prepared molecular cage by an exchange strategy, that is, mixing the already prepared organic molecular cage with other alcohols and reacting under solvothermal conditions to obtain an organic molecular cage with that alcohol.

9. According to the preparation method of claim 8, the molar ratio of the amounts of the synthons tetraaldehyde calix[4]resorcinarene, aminophenylboronic acid, and alcohol synthon is 1:(3-6):(3-60), and an example is 1:4:

24. Preferably, the temperature of the reaction is 60-100 °C, such as 80 °C, 100 °C; the reaction time is 12-48 h, such as 24 h. Preferably, the reaction is carried out in an organic solvent. For example, the organic solvent can be N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMA), N-methylpyrrolidone (NMP), and an example is DMF. Preferably, the preparation method further comprises ultrasonic treatment of the reaction mixture before heating the reaction. Preferably, the ultrasonic treatment time can be 3-15 min. An example is about 5 min. Preferably, the preparation method further includes: The process of collecting the organic molecular cage MPOC compound from the reaction solution after the reaction is completed. Specifically, the process is as follows: at room temperature (10 - 30 °C), the solvent is removed by filtration, and exchanged with a low-polarity solvent (such as n-pentane, n-hexane, petroleum ether) for 2 - 4 days, and the fresh solvent is changed 2 - 4 times every day.

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