CN108586776B

CN108586776B - Preparation of supramolecular polymer gel and metal complex thereof and application of supramolecular polymer gel in ion detection

Info

Publication number: CN108586776B
Application number: CN201810636675.3A
Authority: CN
Inventors: 林奇; 关晓文; 陈燕燕; 王姣; 樊彦青; 姚虹; 张有明; 魏太保
Original assignee: Northwest Normal University
Current assignee: Northwest Normal University
Priority date: 2018-06-20
Filing date: 2018-06-20
Publication date: 2020-12-01
Anticipated expiration: 2038-06-20
Also published as: CN108586776A

Abstract

The inventionDesigned and synthesized a supermolecular polymer gel, which is a column [5] functionalized by naphthalimide in cyclohexanol]Arene (P5N) is used as a host, bis 4,4 bipyridyl salt (G) is used as a guest, and the host and the guest are self-assembled in an equimolar ratio to form the supermolecular polymer TDPG with yellow aggregation state induced fluorescence. Adding various cations, only Fe, into the supermolecular polymer TDPG³⁺、Hg²⁺Can quench the fluorescence of the supramolecular polymer gel, and can be used for fluorescence recognition and adsorption separation of Fe in solution³⁺And Hg²⁺. Respectively adding Fe into the supermolecular polymer TDPG³⁺And Hg²⁺To obtain stable metal supermolecule complexes Fe-TDPG and Hg-TDPG, which can detect and identify F with high sensitivity and high selectivity^‑And Br^‑. The identification performance has important application value in the field of ion identification.

Description

Preparation of supramolecular polymer gel and metal complex thereof and application of supramolecular polymer gel in ion detection

Technical Field

The invention relates to a supermolecule polymer gel, in particular to a supermolecule polymer gel which is assembled by taking naphthalimide functionalized column [5] arene as a main body and bis (4, 4-bipyridyl) salt as an object; the invention also relates to metal complexes based on the supramolecular polymer gel; the invention relates to a supramolecular polymer gel and application of a metal complex thereof in ion detection.

Background

Ions and molecules play an important role in the fields of chemistry, biology, environment and the like, and are important for the detection and separation of certain specific ions or molecules in the environment. At present, various ion/molecule detection methods have been developed, and fluorescence methods have been developed as the main detection means for ion identification due to their advantages of simple operation, rapidness, high sensitivity, and the like. However, in real life, various ions which are beneficial or harmful to human bodies mostly exist in the water phase, and most of reported methods for detecting the ions are carried out in solution, so that the detection of the ions is relatively limited; and fluorine ions and the like have larger hydration energy, and are difficult to detect in a water phase.

Disclosure of Invention

The object of the present invention is to provide a supramolecular polymer gel;

it is another object of the present invention to provide a metal complex based on the above supramolecular polymer gel;

the invention also aims to provide the application of the supramolecular polymer gel and the metal supramolecular complex thereof in ion detection.

Mono-and supramolecular polymer gels

The supramolecular polymer gel is formed by assembling column [5] arene (P5N) with a main body of naphthylimide functionalized and guest double 4,4 bipyridyl salt (G) in a cyclohexanol according to an equimolar ratio, and is marked as TDPG.

Wherein the structural formula of the main body naphthalimide functionalized column [5] arene (P5N) is as follows:

n=1、2、3、4；

the structure of guest bis 4,4 bipyridinium salt (G) is as follows:

the assembly mode of the subject and the object is as follows:

the mechanism of formation of the supramolecular polymer gel TDPG is analyzed by a nuclear magnetic map and a nuclear magnetic titration hydrogen spectrogram. FIG. 1 is a partial concentration nuclear magnetic map of P5N. In FIG. 1, the concentration of P5N gradually increases from (b) to (g), and H1-7 is found to move to a high field, which indicates that the column aromatic hydrocarbon group and the naphthalimide group of P5N have pi-pi action with another molecule P5N. FIG. 2 shows the NMR spectra of P5N and G. Wherein (a) P5N; (b) the (h) contains G in different equivalent weights. As can be seen from fig. 2, the hydrogen protons Ha, Hb, Hc, Hd and He on the guest G all shift to a low field, while the hydrogen protons H6 and H7 on the bulk of the pillared arene of host P5N shift to a high field, indicating that the pyridinium moiety of guest G enters the cavity of the pillared arene. These phenomena indicate that the host P5N and the guest G are assembled by host-guest recognition and pi-pi interaction, and a supramolecular polymer scaffold (TDPG) is obtained.

Fluorescent responsivity of di-or supermolecule polymer TDPG

1. Fluorescence properties of TDPG

Fig. 3 shows the fluorescence spectrum of the supramolecular polymer TDPG. As can be seen from FIG. 3, the supramolecular polymer TDPG has good fluorescence properties, and emits yellow fluorescence (emission wavelength 538 nm) when the excitation wavelength is 350 nm.

2. TDPG vs Fe³⁺And Hg²⁺Fluorescent recognition property of

Adding 10 times of equivalent of Mg into the supermolecular polymer TDPG²⁺，Ca²⁺，Cr³⁺，Fe³⁺，Co²⁺，Ni²⁺，Cu²⁺，Zn²⁺，Ag⁺，Cd²⁺，Hg²⁺，Pb²⁺，Ba²⁺，Al³⁺，La³⁺，Eu³⁺(0.1M) solution, it was found that only Fe was added³⁺And Hg²⁺Can quench the fluorescence of TDPG, so that TDPG can be used for specifically and selectively identifying Fe in solution by fluorescence³⁺And Hg²⁺。

Fluorescence titration experiments show that the supermolecular polymer TDPG is used for Fe³⁺And Hg²⁺Respectively has a minimum detection limit of 9.19 × 10^-9M、3.95×10^-8M (see fig. 3c and 3 d).

3. TDPG vs Fe³⁺And Hg²⁺Fluorescent recognition principle of

The infrared experiment shows that Fe is added into TDPG³⁺When the peak of TDPG is represented by 2923 cm, the peak of-C = H and the peak of-C = O^-1And 1632 cm^-1Moved to 2930 cm^-1And 1668 cm^-1(see FIG. 4), illustrating Fe³⁺And the naphthalimide of P5N has cation-pi interaction, so that a stable complex is formed. When Hg is added²⁺When the-C = N peak of the guest G pyridyl group is 1461 cm^-1Moved to 1457 cm^-1In addition (see FIG. 5), Hg is explained²⁺Coordinate with the nitrogen atom of the pyridine of G to form a stable complex.

Because the supramolecular polymer TDPG can react with Fe³⁺And Hg²⁺The complex is formed by coordination of various chemical bonds, so that the TDPG can realize the coordination to Fe in solution³⁺And Hg²⁺High efficiency separation and removal.

Tetra, metal supermolecule complex

1. Synthesis of metal supramolecular complexes

Respectively adding 2 times of molar weight of Fe into the supermolecular polymer TDPG³⁺And Hg²⁺And heating to dissolve, and cooling to room temperature to obtain stable metal supramolecular complex gel marked as Fe-TDPG and Hg-TDPG.

2. Metal supramolecular complex pair F^-And Br^-High sensitivity detection of

Respectively adding Cl into the metal supermolecular complex Fe-TDPG^-，Br^-，I^-，F^-，AcO^-，H₂PO₄ ^-，HSO₄ ^-，N₃ ^-，OH^-，SCN^-，ClO₄ ^-(0.1M) solution, it was found that only F was added^-The fluorescence of Fe-TDPG could be turned on (see FIG. 4 a).

Respectively adding Cl into metal supermolecular complex Hg-TDPG^-，Br^-，I^-，F^-，AcO^-，H₂PO₄ ^-，HSO₄ ^-，N₃ ^-，OH^-，SCN^-，ClO₄ ^-(0.1M) solution, it was found that only Br was added^-The fluorescence of Hg-TDPG could be turned on and pink fluorescence emitted (see fig. 4 b).

In conclusion, through a competitive coordination mechanism, a supramolecular polymer framework material (TDPG) and a metal supramolecular polymer framework material (M-TDPG) which are synthesized by the design can realize multi-guest response and high-sensitivity detection and separation of various ions. And the competitive coordination identification can also be used as an 'ON-OFF-ON' type fluorescent switch, and the identification performance has important application value in the field of ion identification.

Drawings

FIG. 1 is a nuclear magnetic hydrogen spectrum of P5N.

FIG. 2 shows the NMR spectra of P5N and G.

FIG. 3 shows TDPG vs Fe³⁺And Hg²⁺Fluorescence titration graph of (a).

FIG. 4 shows TDPG identification of Fe³⁺And Fe-TDPG recognition of F^-An infrared spectrum of (1).

FIG. 5 shows identification of Hg by TDPG²⁺And Hg-TDPG recognition of Br^-An infrared spectrum of (1).

FIG. 6 shows the Fe-TDPG and Hg-TDPG vs F^-And Br^-Fluorescence titration of (4).

Detailed Description

The preparation and use of the supramolecular polymers and metal complexes of the invention are further illustrated by the following specific examples.

Example 1 Synthesis of supramolecular Polymer gel (TDPG)

(1) Synthesis of host P5N: to 50ml of acetonitrile, 0.58g (5X 10) was added^-3mol) brominated column [5]Aromatic P5, 0.43g (1.5X 10)^-3mol) naphthalimide derivative, and reacting for 48h at 80 ℃; after the reaction is finished, cooling to room temperature, removing the solvent by rotary evaporation, mixing the sample with a column, eluting with petroleum ether and ethyl acetate =10: 1-10: 5 (v/v), and obtaining a yellow solid product, namely the gel factor P5N; the yield was 75.6%.

(2) Synthesis of guest G: 1.9801g (1.89 g, 6.3 mmol) of 1, 10-dibromodecane and 4,4' -bipyridine (5.56 g, 35.7 mmol) are added to 100ml of acetonitrile, and the mixture is stirred and refluxed at 90-100 ℃ for 18 hours; and cooling to room temperature, filtering by using a Buchner funnel, and washing for 3-5 times by using acetonitrile and ethanol to obtain 3.3G of pale yellow green powder product, namely guest compound G. The yield was 86%.

(3) Synthesis of supramolecular polymer gel (TDPG): to 0.2ml of cyclohexanol was added bulk P5N (0.0050 g, 4.5X 10)^-6mol), guest G (0.0047G, 4.5X 10^-6mol), heating to completely dissolve the supramolecular polymer gel, and then cooling to room temperature to obtain the stable supramolecular polymer gel (TDPG) with blue fluorescence.

Example 2 supramolecular polymers TDPG vs Fe³⁺And Hg²⁺Fluorescent identification of

Adding 10 times of equivalent of Mg into the supermolecular polymer gel TDPG²⁺，Ca²⁺，Cr³⁺，Fe³⁺，Co²⁺，Ni²⁺，Cu²⁺，Zn²⁺，Ag⁺，Cd²⁺，Hg²⁺，Pb²⁺，Ba²⁺，Al³⁺，La³⁺，Eu³⁺(0.1M) solution, and the change in fluorescence of the solution was observed. As a result, it was found that only Fe was added³⁺、Hg²⁺Then, the fluorescence of TDPG is quenched, thereby Fe³⁺、Hg²⁺Are identified from a plurality of cations.

Example 3 supramolecular polymer gel vs. Fe³⁺And Hg²⁺Efficient separation and removal of

Firstly, the concentration is prepared to be 1 multiplied by 10^-5M Fe³⁺And Hg²⁺5mL of each solution, 0.1mg (5X 10) of each ionic solution was added^-8mol) TDPG xerogel, shaking for 30 minutes, centrifuging at 8000r/min for 20 minutes, and taking the residual supernatant as ICP (inductively coupled plasma). The results show that TDPG is against Hg²⁺And Fe³⁺The adsorption efficiency of the ions is shown in table 1:

。

example 4 preparation and application of Metal supramolecular complexes (M-TDPG)

Two portions of P5N (0.005G) and G (0.005G) were added to 0.5ml of cyclohexanol, and 2 times the equivalent of Fe was added³⁺And Hg²⁺Heating to dissolve and cooling to room temperature to obtain stable metal supermolecular complex Fe-TDPG and Hg-TDPG.

Respectively adding Cl into the metal supermolecular complex Fe-TDPG^-，Br^-，I^-，F^-，AcO^-，H₂PO₄ ^-，HSO₄ ^-，SCN^-，CN^-，ClO₄ ^-If the fluorescence of the metal supramolecular complex Fe-TDPG is recovered, the F is added^-(ii) a If the fluorescence of the metal supermolecular complex Fe-TDPG is not recovered, it indicates that other anions are added.

Respectively adding Cl into metal supermolecular complex Hg-TDPG^-，Br^-，I^-，F^-，AcO^-，H₂PO₄ ^-，HSO₄ ^-，SCN^-，CN^-，ClO₄ ^-If the fluorescence of the metal supramolecular complex Hg-TDPG changes to pink, it indicates that Br is added^-If the fluorescence of the metal supramolecular complex Hg-TDPG is not changed, the addition is indicated to be other anions.

Claims

1. A supermolecular polymer gel is prepared by self-assembling column [5] arene functionalized by main body naphthalimide and guest bis 4,4 bipyridyl salt in an equimolar ratio in cyclohexanol to obtain the supermolecular polymer gel with yellow aggregation state induced fluorescence;

the structural formula of the main body naphthalimide functionalized column [5] arene is as follows:

n=1、2、3、4；

the structural formula of the guest bis 4,4 bipyridine salt is as follows:

。

2. the supramolecular polymer gel as claimed in claim 1, wherein: the content of the main body naphthalimide functionalized column [5] arene and the guest bis 4,4 bipyridyl salt in a system is 1.5-2.5 g/mL.

3. Use of the supramolecular polymer gel as claimed in claim 1 for fluorescent recognition of Fe³⁺And Hg²⁺The method is characterized in that: adding Mg into supramolecular polymer gel respectively²⁺，Ca²⁺，Cr³⁺，Fe³⁺，Co²⁺，Ni²⁺，Cu²⁺，Zn²⁺，Ag⁺，Cd²⁺，Hg²⁺，Pb²⁺，Ba²⁺，Al³⁺，La³⁺，Eu³⁺Solution of only Fe³⁺、Hg²⁺Can quench the fluorescence of the supramolecular polymer gel.

4. Use of the supramolecular polymer gel as claimed in claim 1 for adsorptive separation of Fe in solution³⁺And Hg²⁺。

5. A metal supramolecular complex based on the supramolecular polymer gel as claimed in claim 1, wherein Fe is added to the supramolecular polymer gel in an amount of 2 times the molar weight of the supramolecular polymer³⁺、Hg²⁺And heating to dissolve, and cooling to room temperature to obtain stable metal supramolecular complex gels Fe-TDPG and Hg-TDPG.

6. Use of the metallo-supramolecular complexes according to claim 5 for the recognition of F^-The method is characterized in that: respectively adding Cl into the metal supermolecular complex Fe-TDPG^-，Br^-，I^-，F^-，AcO^-，H₂PO₄ ^-，HSO₄ ^-，SCN^-，CN^-，ClO₄ ^-If the fluorescence of the metal supramolecular complex Fe-TDPG is recovered, the F is added^-(ii) a If the fluorescence of the metal supermolecular complex Fe-TDPG is not recovered, it indicates that other anions are added.

7. Use of the metallo-supramolecular complexes of claim 5 for the recognition of Br^-The method is characterized in that: respectively adding Cl into metal supermolecular complex Hg-TDPG^-，Br^-，I^-，F^-，AcO^-，H₂PO₄ ^-，HSO₄ ^-，SCN^-，CN^-，ClO₄ ^-If the fluorescence of the metal supramolecular complex Hg-TDPG changes to pink, it indicates that Br is added^-If the fluorescence of the metal supramolecular complex Hg-TDPG is not changed, the situation that other anions are added is indicated.