CN113214494B

CN113214494B - Spiral supramolecular material and preparation method and application thereof

Info

Publication number: CN113214494B
Application number: CN202110555206.0A
Authority: CN
Inventors: 王明; 于浩; 蒋鑫
Original assignee: Jilin University
Current assignee: Jilin University
Priority date: 2021-05-21
Filing date: 2021-05-21
Publication date: 2022-05-31
Anticipated expiration: 2041-05-21
Also published as: CN113214494A

Abstract

A helical supramolecular material and a synthesis method and application thereof of the present invention belong to the technical field of supramolecular chemistry. The helical supramolecular material is a helical structure complex composed of a polydentate terpyridine (tpy) ligand molecule and a transition metal M, and the main steps of the preparation method include: synthesis of compound Z and synthesis of polydentate terpyridine ligand. , synthesis of multi-helix supramolecular materials, etc., the helical supramolecular materials can be used as host and guest calix[n]arene for host-guest recognition. The present invention assembles polydentate terpyridine ligands and transition metals, and utilizes the feature of terpyridine coordination angle of 180° to obtain multi-helix supramolecules with different cavity sizes and different spatial constraints. Structural features de-specifically recognize guest molecules, which makes the host-guest system more complete.

Description

Spiral supramolecular material and preparation method and application thereof

Technical Field

The invention belongs to the technical field of supermolecule chemistry, and relates to synthesis of a material with a multi-helix supermolecule structure, which can be applied to subject-object recognition of calix [ n ] arene (n ═ 4-8).

Background

The concept of supramolecular chemistry was proposed in the past 70 s and has now evolved as an important branch of the chemical field. Non-covalent interactions are the basis for the study of supramolecular chemistry, including hydrogen bonds, ionic bonds, pi-pi stacking, coordination bonds, hydrophilicity and hydrophobicity, and the like. Among them, the metal-ligand coordination-driven molecular self-assembly has become one of the most effective strategies for constructing precise discrete supramolecular assemblies due to proper bond energy and guidance. As for polypyridine ligands and various derivatives of pyridine, because nitrogen atoms in the polypyridine ligands contain fixed lone-pair electrons, the pyridine ligands can generate coordination with various metal salts, and the pyridine supermolecular structure greatly enriches the content of a supermolecular system and is one of the classical systems in coordination chemistry. One of the commonly used pyridine building blocks is terpyridine (tpy), and terpyridine derivatives have attracted considerable attention in the field of supramolecular self-assembly due to their strong binding ability to different naked transition metal ions. Many two-dimensional structures have been successfully constructed by coordination of a tripyridyl ligand to a metal ion, and the complexity and novelty of these structures is increasing. However, since the coordination angle between terpyridine and metal ions is generally fixed at 180 °, it is still a difficult problem to coordinate terpyridine-based ligands with metals into precisely controllable three-dimensional supramolecular structures, which limits the application of terpyridine coordination in three-dimensional supramolecular structures. In the design, a multidentate terpyridine ligand is designed, and in order to reduce steric hindrance of terpyridine octahedral coordination, a terpyridine unit is designed to the center of a final structure. A series of three-dimensional helical supramolecular structures were successfully synthesized by the assembly of these ligands and transition metals.

Of the many supermolecular systems, host-guest recognition systems have been receiving wide attention in the past decades, and applications of host-guest recognition include targeted recognition of specific guest molecules, purification of mixtures, generation of novel asymmetric catalytic pathways, and the like. The three-dimensional metal organic supermolecular system has good structural stability and has a special internal cavity and an easily-modified functional group ligand, so that a proper assembly element is designed, and the cavity of the three-dimensional molecular cage is accurately regulated and controlled, so that the three-dimensional metal organic supermolecular system can specifically identify and package a specified object, and is one of research hotspots of the three-dimensional metal organic supermolecular system. In the encapsulation study of supramolecular guest molecules, most studies focus on the guest in a regular structure, such as polyaromatic hydrocarbons and fullerenes, and there are few reports of studies using calixarenes having a complex conformation as the guest. Therefore, the research of the host-object recognition of the calixarene by using the three-dimensional metal organic supermolecule has great value.

The main principle of host-guest recognition of three-dimensional metal organic supramolecules is as follows: firstly, three-dimensional metal organic supermolecules provide cavities with proper sizes and proper space limitation to contain and restrain object molecules, and secondly, host-object structures are formed between the supermolecule host and the objects through one or more non-covalent acting forces, wherein the acting forces comprise pi-pi acting forces, electrostatic acting forces, hydrophobic acting forces and the like. Good size and shape matching between the cavity of the three-dimensional metal organic supermolecule and the object is very important, the narrow cavity of the host can limit the movement of the object in the three-dimensional supermolecule host, and the overlarge cavity of the host can weaken van der Waals acting force and electrostatic attraction between the host and the object. Therefore, the host-guest interaction is performed on the objects with different sizes and shapes through the three-dimensional supermolecules with proper cavity sizes.

However, there have been reported host-guest systems that have been deficient in regulating the size of the cavity and the overall spatial constraints of three-dimensional metalorganic supramolecular hosts, which has resulted in the failure of guests with complex conformations like calixarenes to be recognized by suitable hosts, making the host-guest systems deficient.

Disclosure of Invention

The invention aims to solve the technical problem of overcoming the defects of the existing host-object system, and provides a three-dimensional multi-helix supramolecular material with different space limitations and different cavity sizes, a synthetic method of the multi-helix supramolecular material and application of the multi-helix supramolecular material in the aspect of specific recognition of calix [ n ] arene (n ═ 4-8) objects as a host.

The technical problem is solved by the following technical scheme:

a spiral supermolecular material is a complex with a spiral structure, which is composed of multidentate terpyridine (tpy) ligand molecules and transition metal M, and has the following molecular structure:

in the above structure, M represents a transition metal,

represents a tridentate terpyridine ligand molecule;

represents a tetradentate terpyridine ligand molecule;

represents a pentadentate terpyridine ligand molecule;

represents a hexadentate terpyridine ligand molecule.

Preferably, the transition metal M may be one of Zn, Cd, Fe, Ru, Hg, Cu, Ag, Au, Ni, Pd, Pt, Co, Rh, Ir, Os, Mn, Tc and Re.

As a matter of preference,

is one of the following structures A, B, C;

is one of the following structures D, E, F, G;

the structure of (b) is one of the following H, I;

is one of the following J, K:

more preferably, the substituent R in the structure of the multidentate terpyridine ligand molecule is hydrogen, alkoxy or ether oxygen; r₁、R₂Is hydrogen or alkyl.

A method for preparing spiral supramolecular materials comprises the following steps:

(1) synthesis of Compound Z

The synthesis of multidentate terpyridine (tpy) ligand molecules requires the use of an intermediate compound Z, the synthetic route of which is:

mixing compound X and compound Y, Pd (PPh)₃)₂Cl₂Mixing with sodium carbonate at a molar ratio of 1:1:0.05:6, adding toluene, water and tert-butanol at a volume ratio of 4:2:1 under nitrogen atmosphere, stirring the mixture at 85 deg.C for 12 hr, and reacting with CH₂Cl₂Extracting, and purifying the crude product by column chromatography to obtain a compound Z; the structures of the compound X and the compound Y are as follows:

the synthesis of compound X is described in Yi-Tsu Chan, Dalton Trans.2015,44(11), 5139-5145;

(2) synthesis of multidentate terpyridine ligands

Compound Z, ligand-centered nucleus compound, Pd (PPh)₃)₂Cl₂Mixing with sodium carbonate, adding toluene, water and tert-butanol at a volume ratio of 4:2:1 under nitrogen atmosphere, stirring at 85 deg.C for 3-6 days, and reacting with CHCl₃Extracting, and purifying the crude product by column chromatography to obtain a polydentate terpyridine ligand; wherein when the ligand-centered nucleus compound is selected from one of a, b and c, the compound Z, the ligand-centered nucleus compound and Pd (PPh)₃)₂Cl₂The reaction molar ratio of the sodium carbonate to the sodium carbonate is 3:1:0.15:6, and the finally obtained ligand structures are A, B, C respectively; when the ligand-centered nucleus compound is selected from one of d, e, f and g below, the compound Z, the ligand-centered nucleus compound and Pd (PPh)₃)₂Cl₂The reaction molar ratio of the sodium carbonate to the sodium carbonate is 4:1:0.2:6, and the structures of the finally obtained ligands are D, E, F, G respectively; when the ligand-centered nucleus compound is selected from one of h and i, the compound Z, the ligand-centered nucleus compound, Pd (PPh)₃)₂Cl₂The reaction molar ratio of the sodium carbonate to the sodium carbonate is 5:1:0.25:6, and the structures of the finally obtained ligands are H, I respectively; when the ligand-centered nucleus compound is selected fromJ and k below, compound Z, ligand-centered nucleus compound, Pd (PPh)₃)₂Cl₂The reaction molar ratio of the sodium carbonate to the sodium carbonate is 6:1:0.3:6, and the structures of the finally obtained ligands are J, K respectively;

(3) synthesis of multi-helix supramolecular materials

Dissolving the multidentate terpyridine ligand obtained in the step (2) and a transition metal M salt in chloroform or a polar solvent, reacting for 8-24h at the temperature of 50-125 ℃, adding a poor solvent to separate out after the reaction is finished, and centrifuging to obtain a multi-spiral supermolecule; the polar solvent is CH₃CN、DMSO、CH₃OH, DMF, etc.; the poor solvent is determined according to properties of multi-helix supramolecular, and can be selected from diethyl ether and water; when different multidentate terpyridine ligands are used, the molar ratios of ligand to transition metal M are: the reaction molar ratio of the tridentate terpyridine ligand to the transition metal M is 2:3, the reaction molar ratio of the tetradentate terpyridine ligand to the transition metal M is 2:4, the reaction molar ratio of the pentadentate terpyridine ligand to the transition metal M is 2:5, and the reaction molar ratio of the hexadentate terpyridine ligand j to the transition metal M is 2: 6.

Use of a helical supramolecular material, characterized in that it is used with a cup [ n ]]Performing subject-object recognition on aromatic hydrocarbons, wherein n is an integer from 4 to 8, and the operation method comprises the following steps: dissolving the spiral supermolecule material and guest molecules in a polar solvent, and carrying out ultrasonic treatment on the obtained mixed solution to obtain the spiral supermolecule encapsulating cup [ n ]]A host-guest system of an aromatic guest; the polar solvent is CH₃CN, DMSO, DMF, etc.; the cup [ n ]]The structure of the aromatic hydrocarbon is shown as follows, and the substituent R₁、R₂Is hydrogen or alkyl;

has the advantages that:

1. the invention forms a three-dimensional spiral supermolecular structure by synthesizing a multidentate terpyridine ligand, assembling the multidentate terpyridine ligand and transition metal and utilizing the characteristic that the coordination angle of the terpyridine is 180 degrees.

2. The helical supramolecules synthesized by the present invention recognize and encapsulate calix [ n ] arenes (n ═ 4-8) with complex molecular conformations, which are rare in reported subject-object studies.

3. The invention provides multi-spiral supermolecules with different cavity sizes and different space limitations, and each spiral supermolecule can specifically recognize object molecules according to the structural characteristics of the spiral supermolecule, so that a host-object system is more complete.

Description of the drawings:

FIG. 1 is a graph of the hexadentate terpyridine ligand LA prepared in example 1¹H NMR chart.

FIG. 2 is a graph of the hexadentate terpyridine ligand LA prepared in example 1¹³C NMR chart.

FIG. 3 is a 2D COSY NMR chart of hexadentate terpyridine ligand LA prepared in example 1.

FIG. 4 is a MALDI-TOF mass spectrum of hexadentate terpyridine ligand LA prepared in example 1.

FIG. 5 is a diagram of the six-helical supramolecular SA prepared in example 1¹H NMR chart.

FIG. 6 is a diagram of the hexahelical supramolecules SA prepared in example 1¹³C NMR chart.

Figure 7 is a 2D COSY NMR chart of the six-helical supramolecules SA prepared in example 1.

Figure 8 is a 2D DOSY NMR chart of the hexahelical supramolecules SA prepared in example 1.

Figure 9 is an electrospray mass spectrum of different charges of the hexahelical supramolecules SA prepared in example 1 (experimental isotope signal-lower; simulated isotope signal-upper).

Fig. 10 is a crystal structure diagram of the hexahelical supramolecular SA prepared in example 1.

FIG. 11 is a diagram of the six-helix supramolecules SA in example 2¹H NMR chart (a) and encapsulating cup [6]]Method for preparing host-guest complex SA2 after aromatic hydrocarbon¹Comparison of H NMR chart (b).

FIG. 12 is the electrospray mass spectrum (experimental isotope signal-lower; simulated isotope signal-upper) of the different charges of the host-guest complex SA2 in example 2.

FIG. 13 is a photograph of a tridentate terpyridine ligand LB prepared in example 3¹H NMR chart.

FIG. 14 is a MALDI-TOF mass spectrum of tridentate terpyridine ligand LB prepared in example 3.

FIG. 15 is a diagram of the triple-helical supramolecules SB prepared in example 3¹H NMR chart.

FIG. 16 is the electrospray mass spectrum of different charges of the triple-helical supramolecules SB prepared in example 3 (experimental isotope signal-lower; simulated isotope signal-upper).

FIG. 17 is a diagram of the triple-helical supramolecules SB of example 4¹H NMR chart (a) and encapsulating cup [4]]Process for preparing host-guest complex SB2 after aromatic hydrocarbon¹Comparison of H NMR chart (b).

FIG. 18 is a representation of the triple-helical supramolecules SB of example 4¹H NMR chart (a) and encapsulating cup [6]]Process for preparing host-guest complex SB3 after aromatic hydrocarbon¹Comparison of H NMR chart (b).

Detailed Description

Example 1: synthesis of hexahelical supramolecular SA

The synthetic route of the hexadentate terpyridine ligand LA is as follows:

wherein the compound 1 (Xiaoopeng Li, J.Am.chem.Soc.2017,139(24),8174-8185), the compound 2(Yi-Tsu Chan, Dalton Trans.2015,44(11),5139-5145), the compound 4(MikioYasutake, Tetrahedron 2015,71(29),4714-4721), the compound 5 (Pattelis N.Trikalitis, J.Am.chem.Soc.2016,138(39), 12767-12712712770) are prepared by synthesis according to the relevant references.

Synthesis of Compound 3:

compound 2(2.0g, 4.3mmol), bis (pinacol) 1, 4-benzenediboronate (4.3g, 13.0mmol), Pd (PPh)₃)₂Cl₂(151.4mg, 0.22mmol) and sodium carbonate (3.18g, 30mmol) were charged to a 200mL Schlenk flask. Nitrogen was purged three times under vacuum and toluene (60mL), water (30mL) and t-butanol (15mL) were added under nitrogen. The mixture was stirred at 85 ℃ for 12 hours. After cooling to room temperature, the solvent was removed in vacuo and the residue was taken up with CH₂Cl₂And (4) extracting. Through anhydrous Na₂SO₄Drying and then spin-drying the solvent in vacuo and the crude product was purified by silica gel column chromatography with dichloromethane: ethanol (100: 1.5) as eluent gave compound 3 as a white solid (1.2g, 47.6%).¹H NMR(500MHz,CDCl₃,298K):δ8.74–8.71(m,4H,tpy-H^3′,5′and tpy-H^6,6″),8.67(dt,J＝8.0,1.1Hz,2H,tpy-H^3,3″),7.87(td,J＝7.7,1.8Hz,2H,tpy-H^4,4″),7.82–7.75(m,2H,Ph-H^a),7.69(d,J＝8.1Hz,2H,Ph-H^b),7.52–7.42(m,4H,Ph-H^c,Ph-H^d,Ph-H^e and Ph-H^f),7.34(ddd,J＝7.5,4.8,1.2Hz,2H,tpy-H^5,5″),7.31–7.27(m,2H,Ph-H^g),7.20(d,J＝8.1Hz,2H,Ph-H^h),1.33(s,12H,Hⁱ).

Synthesis of hexadentate terpyridine ligand LA:

compound 3(1.5g, 2.6mmol), hexa (4-bromophenyl) -benzene (328mg, 0.33mmol), Pd (PPh)₃)₂Cl₂(91mg, 0.13mmol) and sodium carbonate (1.59g, 15mmol) were poured into a 100mL Schlenk flask. Toluene (30mL), water (15mL) and t-butanol (7mL) were added under nitrogen. The mixture was stirred at 85 ℃ for 6 days. After cooling to room temperature, the solvent was removed in vacuo and the residue was taken up in CHCl₃And (4) extracting. The combined organic layers were washed with brine, over anhydrous Na₂SO₄Drying, concentrating under vacuum, and purifying the crude product by silica gel column chromatographyPurification, with dichloromethane: ethanol (100: 3.5) was used as eluent to give the product, hexadentate terpyridine ligand LA (0.47g, 43%) as a white solid.¹H NMR(500MHz,CDCl₃,298K)δ8.59(s,12H,tpy-H^3′,5′),8.58–8.55(m,12H,tpy-H^6,6″),8.51(d,J＝8.0Hz,12H,tpy-H^3,3″),7.74(td,J＝7.7,1.8Hz,12H,tpy-H^4,4″),7.64(d,J＝8.1Hz,12H,Ph-H^a),7.43–7.34(m,18H,Ph-H^c,Ph-H^dand Ph-H^e),7.30(d,J＝7.4Hz,6H,Ph-H^f),7.29(s,12H,Ph-H^j),7.19(ddd,J＝7.5,4.7,1.2Hz,12H,tpy-H^5,5″),7.15(d,J＝8.0Hz,12H,Ph-H^b),7.11(d,J＝8.0Hz,12H,Ph-H^h),6.99(d,J＝8.1Hz,12H,Ph-Hⁱ),6.86(d,J＝8.0Hz,12H,Ph-H^g).MALDI-TOF MS(m/z):Calcd.for[C₂₄₀H₁₅₆N₁₈]⁺3289.3.Found:3289.3

FIG. 1 is of hexadentate terpyridine ligand LA¹H NMR chart, FIG. 2 is of LA¹³C NMR chart. The H signal of LA was assigned by the 2D COSY NMR spectrum in fig. 3. MALDI-TOF mass spectrum of FIG. 4 confirmed that the molecular weight of LA was 3289.29 Da. The above characterization is sufficient to demonstrate the synthesis of the hexadentate terpyridine ligand LA.

To hexadentate terpyridine ligand LA (6.0mg, 1.82. mu. mol) in CHCl₃(2mL) solution, Zn (NO) was added₃)₂·6H₂O (1.6mg, 5.4. mu. mol) in MeOH (6 mL). The mixture was reacted at 50 ℃ for 8h and then cooled to room temperature. Addition of NH₄PF₆After (80mg), the precipitate was allowed to stand and washed with water to give the white product SA (7.1mg, 90%). The reaction process is as follows:

FIG. 5 is a six-helix supramolecular SA¹H NMR spectrum, showing only one set of product peaks, indicating that assembly produces a single product. FIG. 6 is a schematic view of¹³The C NMR chart again demonstrates the formation of assembly SA. H signal of SA by 2D COSY NMR spectrum of FIG. 7Detailed attribution was made. The 2D DOSY NMR spectrum of fig. 8 clearly shows a band (log D ═ 9.43), again confirming the formation of a single product. FIG. 9 is an electrospray mass spectrogram of different charges of hexa-helical supramolecular SA, which shows a group of (5+ to 9+) peaks with molecular weight of 8714.3Da, and the isotope signals measured by the experiment can be well matched with the simulated isotope signals. FIG. 10 is a crystal structure diagram of a six-helix supramolecular SA, which can be seen to consist of two parallel hexadentate ligands LA and six Zn (II), and shows a relatively crowded structure, with a 63 ° connection angle between the faceplate and the terpyridine, with the diameter and height of the faceplate, respectively

And

by the above characterization, the formation of hexahelical supramolecules SA can be fully demonstrated.

Example 2: host-guest recognition of calix [6] arene by hexa-helix supramolecular SA

The crystal structure of SA clearly indicates a certain cavity in the cage and a larger pi-conjugated panel. In addition, the steric hindrance of terpyridine provides an essential help for the closure of the cavity, which makes it possible to explore the recognition of guest molecules. To facilitate the cup [6] at room temperature]Dissolving aromatic hydrocarbon, and mixing CD₃CN and CDCl₃The mixture of (3: 1) was used as a solvent. SA is mixed with a cup [6]]Aromatic hydrocarbons were mixed, sonicated for 60min and found by adding excess of cup [6]]The hydrogen signal of the aromatic hydrocarbon, SA, showed a shift as shown in fig. 11, which indicates the formation of host-guest complex SA 2. FIG. 12 is an electrospray mass spectrum of different charges of the host-guest composite SA2, showing a set of (5+ to 8+) peaks with a molecular weight of 9988.8Da, indicating that two cups [6] are encapsulated in the host-guest composite SA2]An aromatic hydrocarbon. By the above characteristics, it can be fully proved that the six-helix supermolecule SA pairs [6]]And (3) recognizing the host and the object of the aromatic hydrocarbon.

Example 3: synthesis of triple-helical supramolecules SB

The synthetic route of tridentate terpyridine ligand LB is shown in the following, wherein compound 1 (Xiaoopeng Li, J.am.chem.Soc.2017,139(24),8174-8185), compound 2(Yi-Tsu Chan, Dalton trans.2015,44(11),5139-5145) are prepared by synthesis according to related documents, and the synthesis of compound 3 is shown in example 1.

Synthesis of tridentate terpyridine ligand LB:

compound 3(1.2g, 2.0mmol), 1,3, 5-tris (4-bromophenyl) benzene (0.31g, 0.57mmol), Pd (PPh)₃)₂Cl₂(70mg, 0.1mmol) and sodium carbonate (1.59g, 15mmol) were charged to a 100mL Schlenk flask. Toluene (30ml), water (15ml) and tert-butanol (5ml) were added under nitrogen. The mixture was stirred at 85 ℃ for 3 d. After cooling to room temperature, the solvent was removed in vacuo and the residue was taken up in CHCl₃And (4) extracting. The combined organic layers were washed with brine, over anhydrous Na₂SO₄Dried and then concentrated in vacuo and the crude product purified by silica gel column chromatography, eluting with dichloromethane: ethanol (100: 2.5) was used as eluent to give the product tridentate terpyridine ligand LB (0.62g, 65%) as a white solid.¹H NMR(500MHz,CDCl₃,298K)δ8.73(s,6H,tpy-H^3′,5′),8.69(dd,J＝4.9,1.7Hz,6H,tpy-H^6,6″),8.65(d,J＝7.9Hz,6H tpy-H^3,3″),7.87–7.79(m,15H,tpy-H^4,4″,Ph-H^k and Ph-H^a),7.75(m,12H,Ph-H^j and Ph-Hⁱ),7.57(d,J＝8.0Hz,6H,Ph-H^h),7.54-7.52(m,6H,Ph-H^d and Ph-H^c),7.51–7.46(m,6H,Ph-H^f and Ph-H^e),7.35(d,J＝8.2Hz,6H,Ph-H^b),7.30(m,12H,tpy-H^5,5″and Ph-H^g).MALDI-TOF MS(m/z):Calcd.for[C₁₂₃H₈₁N₉]⁺1683.7.Found:1683.7

FIG. 13 is of tridentate terpyridine ligands LB¹H NMR chart, MALDI-TOF mass spectrum of FIG. 14 confirmed the molecular weight of LB was 1683.66 Da. The above characterization demonstrates the synthesis of tridentate terpyridine ligand LB.

To tridentate terpyridine ligand LB (10.0mg, 5.9. mu. mol) in CHCl₃(3mL) to the solution, Zn (NO) was added₃)₂·6H₂O (2.6mg, 8.9. mu. mol) in MeOH (9 mL). The mixture was reacted at 50 ℃ for 8h and then cooled to room temperature. Addition of NH₄PF₆After (100mg), the precipitate was left to stand and washed with water to give a white product SB (11.8mg, 90%). The reaction process is as follows:

FIG. 15 is a triple helix supramolecular SB¹H NMR spectrum showing only one set of product peaks, indicating that assembly results in a single product. FIG. 16 is an electrospray mass spectrogram of different charges of triple-helix supramolecules SB, which shows a group of (3+ to 6+) peaks with the molecular weight of 5637.2Da, and the isotope signals measured by the experiment can be well matched with the simulated isotope signals. By the above characterization, the formation of triple-helical supramolecules SB can be demonstrated.

Example 4: host-guest recognition of calix [4] arene and calix [6] arene by three-helix supramolecule SB

The triple helix supramolecule SB was mixed with calix [4] arene in acetonitrile and sonicated for 60min, and it was found that by adding excess calix [4] arene, the hydrogen signal of SB showed some shift, as shown in figure 17, indicating the formation of host-guest complex SB 2. In the same way, SB was mixed with excess calix [6] arene in acetonitrile and sonicated for 60min, the hydrogen signal of SB showed some shift, as shown in figure 18, indicating the formation of the host-guest complex SB 3. Through the nuclear magnetic characterization, the recognition of the three-helix supermolecule SB on the host and the guest of the calix [4] arene and the calix [6] arene can be proved.

Claims

1. A spiral supramolecular material is a complex with a spiral structure, which is composed of multidentate terpyridine ligand molecules decorated at ortho-position of a benzene ring and transition metal M, and has the following molecular structure:

in the above structure, M represents a transition metal;

represents a tridentate terpyridine ligand molecule, and the structure of the tridentate terpyridine ligand molecule is one of A, B, C below;

represents a tetradentate terpyridine ligand molecule, and the structure of the tetradentate terpyridine ligand molecule is one of D, E, F, G below;

represents a pentadentate terpyridine ligand molecule with the structure of one of H, I below;

represents a hexadentate terpyridine ligand molecule having the structure of one of J, K:

2. a helical supramolecular material as claimed in claim 1, wherein said transition metal M is selected from one of Zn, Cd, Fe, Ru, Hg, Cu, Ag, Au, Ni, Pd, Pt, Co, Rh, Ir, Os, Mn, Tc, Re.

3. A helical supramolecular material as claimed in claim 1, wherein substituents R in the structure of multidentate terpyridine ligand molecules are hydrogen, alkoxy or etheroxy; r₁、R₂Is hydrogen or alkyl.

4. A method for the preparation of helical supramolecular materials as claimed in claim 1, comprising the steps of:

(1) synthesis of Compound Z

The synthesis of the multidentate terpyridine ligand molecule needs to use an intermediate compound Z, and the synthetic route of the compound Z is as follows:

(2) synthesis of multidentate terpyridine ligands

Compound Z, ligand-centered nucleus compound, Pd (PPh)₃)₂Cl₂Mixing with sodium carbonate, adding toluene at a volume ratio of 4:2:1 in a nitrogen atmosphere,Water and tert-butanol, stirring the mixture at 85 deg.C for 3-6 days, and adding CHCl₃Extracting, and purifying the crude product by column chromatography to obtain a polydentate terpyridine ligand; wherein when the ligand-centered nucleus compound is selected from one of a, b and c, the compound Z, the ligand-centered nucleus compound and Pd (PPh)₃)₂Cl₂The reaction molar ratio of the sodium carbonate to the sodium carbonate is 3:1:0.15:6, and the finally obtained ligand structures are A, B, C respectively; when the ligand-centered nucleus compound is selected from one of d, e, f and g below, the compound Z, the ligand-centered nucleus compound and Pd (PPh)₃)₂Cl₂The reaction molar ratio of the sodium carbonate to the sodium carbonate is 4:1:0.2:6, and the structures of the finally obtained ligands are D, E, F, G respectively; when the ligand-centered nucleus compound is selected from one of h and i, the compound Z, the ligand-centered nucleus compound, Pd (PPh)₃)₂Cl₂The reaction molar ratio of the sodium carbonate to the sodium carbonate is 5:1:0.25:6, and the structures of the finally obtained ligands are H, I respectively; when the ligand-centered nucleus compound is selected from one of j and k, the compound Z, the ligand-centered nucleus compound and Pd (PPh)₃)₂Cl₂The reaction molar ratio of the sodium carbonate to the sodium carbonate is 6:1:0.3:6, and the structures of the finally obtained ligands are J, K respectively;

(3) synthesis of multi-helix supramolecular materials

Dissolving the multidentate terpyridine ligand obtained in the step (2) and a transition metal M salt in chloroform or a polar solvent, reacting for 8-24h at the temperature of 50-125 ℃, adding a poor solvent to separate out after the reaction is finished, and centrifuging to obtain the multi-spiral supramolecular material; the polar solvent is selected from CH₃CN、DMSO、CH₃OH or DMF; the poor solvent is selected from diethyl ether or water; when different multidentate terpyridine ligands are used, the ligand is reacted withThe molar ratio of the transition metal M is respectively as follows: the reaction molar ratio of the tridentate terpyridine ligand to the transition metal M is 2:3, the reaction molar ratio of the tetradentate terpyridine ligand to the transition metal M is 2:4, the reaction molar ratio of the pentadentate terpyridine ligand to the transition metal M is 2:5, and the reaction molar ratio of the hexadentate terpyridine ligand to the transition metal M is 2: 6.

5. Use of a helical supramolecular material as claimed in claim 1, characterized in that said helical supramolecular material is used with a cup [ n ]]Performing subject-object recognition on aromatic hydrocarbons, wherein n is an integer from 4 to 8, and the operation method comprises the following steps: dissolving the spiral supramolecular material and an object molecule in a polar solvent, and carrying out ultrasonic treatment on the obtained mixed solution to obtain the spiral supramolecular encapsulation cup [ n ]]A host-guest system of an aromatic guest; the polar solvent is selected from CH₃CN, DMSO or DMF; the cup [ n ]]The structure of the aromatic hydrocarbon is shown as follows, and the substituent R₁、R₂Is hydrogen or alkyl;