阅读说明：本技术 一种基于螺芴四位点柱[n]芳烃的三维超分子聚合物及其制备方法与应用 (Three-dimensional supramolecular polymer based on spirofluorene four-site column [ n ] arene and preparation method and application thereof ) 是由 曹德榕 王蓉蓉 许林贤 唐浩 汪凌云 于 2020-04-30 设计创作，主要内容包括：本发明公开了一种基于螺芴四位点柱[n]芳烃的三维超分子聚合物及其制备方法与应用。该方法包括：将基于螺芴四位点柱[n]芳烃的主体分子、客体分子1(供体)、客体分子2(受体)溶解在机溶剂、水或者混合溶剂中,形成所述基于主客体相互作用的超分子自组装聚合物。本发明提供的超分子聚合物中,在主体分子与不良溶剂的协同作用下,能量相互匹配的客体分子1(供体)与客体分子2(受体)排列有序而紧密,二者的距离大大缩短,通过天线效应及荧光共振能量转移(FRET)机理,能量可以由客体分子1(供体)高效转移给客体分子2(受体),使三者形成的三维超分子聚合物的荧光强度与相同浓度下客体分子2(受体)的相比有了很大的提升。(The invention discloses a three-dimensional supramolecular polymer based on spirofluorene four-site column [ n ] arene and a preparation method and application thereof. The method comprises the following steps: dissolving host molecules, guest molecules 1 (donor) and guest molecules 2 (acceptor) based on spirofluorene four-site column [ n ] arene in an organic solvent, water or a mixed solvent to form the supermolecule self-assembly polymer based on the host-guest interaction. In the supramolecular polymer provided by the invention, under the synergistic action of a host molecule and a poor solvent, an object molecule 1 (donor) and an object molecule 2 (acceptor) which are mutually matched in energy are orderly and closely arranged, the distance between the two molecules is greatly shortened, and the energy can be efficiently transferred from the object molecule 1 (donor) to the object molecule 2 (acceptor) through an antenna effect and a Fluorescence Resonance Energy Transfer (FRET) mechanism, so that the fluorescence intensity of the three-dimensional supramolecular polymer formed by the three molecules is greatly improved compared with that of the object molecule 2 (acceptor) under the same concentration.)

1. A preparation method of a three-dimensional supramolecular polymer based on spirofluorene four-site column [ n ] arene is characterized by comprising the following steps:

mixing a host molecule, an object molecule 1 and an object molecule 2 based on the spirofluorene four-site column [ n ] arene, and carrying out self-assembly on the host molecule, the object molecule and the object molecule under the interaction of the host and the object to obtain the three-dimensional supramolecular polymer based on the spirofluorene four-site column [ n ] arene.

2. The method for preparing three-dimensional supramolecular polymer based on spirofluorene quadbit [ n ] arene according to claim 1, characterized in that the structural formula of the host molecule based on spirofluorene quadbit [ n ] arene is as follows:

wherein R is₁And R₂All are one of hydroxyl, amino, carboxyl, nitro, ester group, trifluoromethanesulfonyl, straight-chain alkoxy and branched-chain alkoxy; n is an integer, and the value range of n is 4-8; a. the₁Is one or the default of carbon-carbon double bond, carbon-carbon triple bond, triazole and benzene ring; the dotted line in the structural formula represents a column [ n ] on the repeating unit of the host molecule]Aromatic hydrocarbon cyclic structure.

3. The method for preparing three-dimensional supramolecular polymer based on spirofluorene four-site column [ n ] arene, according to claim 2, characterized in that the carbon atoms of the linear alkoxy and branched alkoxy are both 1-12.

4. The method for preparing a three-dimensional supramolecular polymer based on spirofluorene four-site column [ n ] arene, according to claim 1, wherein the structural formula of the guest molecule 1 is as follows:

wherein R is₃Is one of linear alkyl, branched alkyl, benzene ring, cyclohexyl and hydrogen atom; a. the₂Is one of carbon-carbon double bond, benzene ring and carbon-carbon triple bond or is absent; the carbon atoms of the straight-chain alkyl and the branched-chain alkyl are both 1-20.

5. The method for preparing a three-dimensional supramolecular polymer based on spirofluorene four-site column [ n ] arene, according to claim 1, wherein the structural formula of the guest molecule 2 is as follows:

wherein R is₄Is one of thiophene, benzene ring, linear alkyl and branched alkyl; a. the₃Is one of carbon-carbon double bond, carbon-carbon triple bond, benzene ring and cyclohexyl or is absent; the carbon atoms of the straight-chain alkyl and the branched-chain alkyl are both 1-20.

6. The preparation method of three-dimensional supramolecular polymer based on spirofluorene four-site column [ n ] arene, according to claim 1, characterized in that the molar ratio of the host molecule to the guest molecule 1 is 100:10-100: 200; the mole number of the guest molecules 2 is 0.01-10% of that of the guest molecules 1.

7. The method for preparing three-dimensional supramolecular polymer based on spirofluorene quadbit [ n ] arene is characterized in that a host molecule, a guest molecule 1 and a guest molecule 2 based on spirofluorene quadbit [ n ] arene are mixed in a solution state; the mixing comprises the following steps: respectively dissolving a host molecule, an object molecule 1 and an object molecule 2 based on spirofluorene four-site column [ n ] arene in a solvent to obtain corresponding solutions, and then uniformly mixing the three solutions to obtain a mixed solution.

8. Spirofluorene tetra-based according to claim 7Site column [ n ]]The preparation method of the three-dimensional supramolecular polymer of the aromatic hydrocarbon is characterized in that the solvent is more than one of chloroform, aqueous solution, cyclohexane, tetrahydrofuran, dimethyl sulfoxide and toluene, and the concentration of each component in the mixed solution is 0-1.0 mol. L^-1。

9. Three-dimensional supramolecular polymer based on spirofluorene four-site column [ n ] arene, prepared by the preparation method of any one of claims 1 to 8.

10. Use of the three-dimensional supramolecular polymer based on spirofluorene four-site column [ n ] arene as claimed in claim 9 in the preparation of light trapping materials.

Technical Field

The invention relates to the technical field of supramolecular self-assembly materials and artificial light capture materials, in particular to a three-dimensional supramolecular polymer based on spirofluorene four-site column [ n ] arene and a preparation method and application thereof.

Background

Photosynthesis, i.e. the capture, transfer and storage of sunlight by green plants and some photosynthetic bacteria in the form of chemical energy, is the basis for the survival of all organisms. This process occurs in chloroplasts of green plants, where light is absorbed by the chromoprotein complex, which contains a large amount of closely packed chlorophyll, and thus photons can be efficiently obtained. The excitation energy is then transferred between chlorophyll molecules and eventually transferred to the reaction center, and converted into chemical energy. The large concentration of antenna pigments around the reaction center is one of the most significant features of natural light trapping systems, which helps organisms to thrive under low light conditions. In recent years, the rapid expansion of human society, the demand of energy sources is increasing, and the rapid exhaustion of natural non-renewable resources such as coal, natural gas and petroleum also brings with it the serious environmental problems, which provides greater examination for the sustainable development and healthy life of human beings. The search for more renewable resources and clean energy is urgently needed, wherein solar energy is the most economical and clean energy, and can be said to be one of inexhaustible energy, so that more and more attention is being paid to the conversion and utilization of solar energy. Inspired by nature, which mimics the process of collecting sunlight in nature, scientists have begun looking at efficient energy transfer from a donor to an acceptor using the process of Fluorescence Resonance Energy Transfer (FRET). With the development of supramolecular chemistry, supramolecular self-assemblies provide a promising, simple and efficient approach for constructing artificial light capture systems. Self-assemblies are such that a large number of molecules form a regularly arranged, tightly packed supramolecular structure that on the one hand can extend the dimensions from the nanoscale to the macroscopic level and on the other hand the resulting structure provides a channel for the migration of excitation energy between antenna chromophores. Therefore, the preparation of the artificial light capture system based on the supermolecule self-assembly body, more efficient energy transfer efficiency and more obvious antenna effect has important significance.

Since the first appearance of the column [ n ] arene in 2008, the column [ n ] arene has attracted wide attention due to the advantages of a highly symmetrical rigid structure, easiness in synthesis and modification, excellent host and guest properties and the like. A host molecule based on spirofluorene four-site column [ n ] arene and a two-site guest molecule respectively containing a tetraphenylethylene group and a pyrrolopyrroledione group in the structure are designed and synthesized for the first time and are respectively used as a donor and an acceptor, and the donor and the acceptor form a novel three-dimensional supramolecular polymer under the action of the host molecule through supramolecular self-assembly and are applied to the construction of an artificial light capture system.

Disclosure of Invention

In order to prepare a more efficient artificial light capture system, the invention aims to provide a three-dimensional supramolecular polymer based on spirofluorene four-site column [ n ] arene, and a preparation method and application thereof.

The purpose of the invention is realized by at least one of the following technical solutions.

The invention provides a three-dimensional supramolecular polymer based on spirofluorene four-site column [ n ] arene, which is formed by self-assembling a host molecule based on the spirofluorene four-site column [ n ] arene and two guest molecules through host-guest interaction, and is applied to the field of constructing an artificial light capture system.

The host molecular structure is connected with four columnar [ n ] arene structures and an orthogonal spirofluorene structure, the orthogonal spirofluorene structure provides powerful support for forming a three-dimensional supramolecular polymer, and the columnar [ n ] arene structures with excellent host and guest performances are introduced to provide binding sites for host and guest interactions; the structure of the guest molecule 1 (donor) contains a tetraphenylethylene group with a classic aggregation-induced fluorescence enhancement effect, and the tetraphenylethylene group shows excellent green light emission in an aggregation state, so that the phenomenon of aggregation-induced fluorescence quenching is avoided, and the tetraphenylethylene group can be used as a donor of a light capture system; the molecular structure of an acceptor is elaborately designed, a diketopyrrolopyrrole structure is introduced into a guest molecule 2 (acceptor) structure to show yellow light emission, and the diketopyrrolopyrrole structure is matched with donor energy and can be used as an acceptor of a light capture system; meanwhile, cyano-triazole sites strongly combined with the columnar [ n ] arene cavities are introduced into the molecular structures of the donor and the acceptor, and the donor and the acceptor can form three-dimensional supramolecular polymers with more ordered structures under the synergistic effect of the main molecules and poor solvents, so that the FRET efficiency is further improved.

The invention provides a three-dimensional supramolecular polymer based on spirofluorene four-site column [ n ] arene, which is formed by self-assembling orthogonal host molecules, guest molecules 1 (donor) and guest molecules 2 (acceptor).

The invention provides a preparation method of a three-dimensional supramolecular polymer based on spirofluorene four-site column [ n ] arene, which comprises the following steps:

mixing a host molecule based on spirofluorene four-site column [ n ] arene, a guest molecule 1 (donor) and a guest molecule 2 (acceptor), and carrying out self-assembly on the host molecule, the guest molecule and the guest molecule under the interaction of the host and the guest to obtain the three-dimensional supramolecular polymer based on the spirofluorene four-site column [ n ] arene.

Further, the structural formula of the spirofluorene four-site column [ n ] arene-based host molecule is shown as follows:

wherein R is₁And R₂All are one of hydroxyl, amino, carboxyl, nitro, ester group, trifluoromethanesulfonyl, straight-chain alkoxy and branched-chain alkoxy; n is an integer, and the value range of n is 4-8; a. the₁Is one or the default of carbon-carbon double bond, carbon-carbon triple bond, triazole and benzene ring; the dotted line in the structural formula represents a column [ n ] on the repeating unit of the host molecule]Aromatic hydrocarbon cyclic structure.

Further, the number of carbon atoms of the linear alkoxy group and the branched alkoxy group is 1 to 12.

Further, the structural formula of the guest molecule 1 (donor) is shown below:

wherein R is₃Is one of linear alkyl, branched alkyl, benzene ring, cyclohexyl and hydrogen atom; a. the₂Is one of carbon-carbon double bond, benzene ring and carbon-carbon triple bond or is absent; the carbon atoms of the straight-chain alkyl and the branched-chain alkyl are both 1-20.

Further, the structural formula of the guest molecule 2 (receptor) is shown below:

wherein R is₄Is one of thiophene, benzene ring, linear alkyl and branched alkyl; a. the₃Is one of carbon-carbon double bond, carbon-carbon triple bond, benzene ring and cyclohexyl or is absent; the carbon atoms of the straight-chain alkyl and the branched-chain alkyl are both 1-20.

Further, the molar ratio of the host molecule to the guest molecule 1 is 100:10 to 100: 200; the mole number of the guest molecules 2 is 0.01-10% of that of the guest molecules 1.

Further, the host molecule, the guest molecule 1 and the guest molecule 2 based on the spirofluorene four-site column [ n ] arene are mixed in a solution state; the mixing comprises the following steps: respectively dissolving a host molecule, an object molecule 1 and an object molecule 2 based on spirofluorene four-site column [ n ] arene in a solvent to obtain corresponding solutions, and then uniformly mixing the three solutions to obtain a mixed solution.

Further, the solvent is more than one of chloroform, aqueous solution, cyclohexane, tetrahydrofuran, dimethyl sulfoxide and toluene, and the concentration of each component in the mixed solution is 0-1.0 mol. L^-1。

The invention provides a three-dimensional supramolecular polymer based on spirofluorene four-site column [ n ] arene, which is prepared by the preparation method.

The invention provides an application of a three-dimensional supramolecular polymer based on spirofluorene four-site column [ n ] arene in preparation of a light capture material.

The principle of the application of the three-dimensional supramolecular polymer based on the spirofluorene four-site column [ n ] arene is as follows.

(1) The molecular structure of the guest molecule 1 (donor) contains a tetraphenylethylene group with a classic aggregation-induced fluorescence enhancement effect, and the tetraphenylethylene group shows excellent green light emission in an aggregation state, so that the phenomenon of aggregation-induced fluorescence quenching is avoided, and the tetraphenylethylene group can be used as a donor of a light capture system. The diketopyrrolopyrrole structure is introduced into the guest molecule 2 (acceptor) structure to show yellow light emission, and the diketopyrrolopyrrole structure is mutually matched with the energy of the guest molecule 1 (donor) and can be used as an acceptor of a light capture system. When the two are close enough, energy is transferred from the donor to the acceptor, so that the fluorescence of the acceptor is greatly enhanced;

(2) further, cyano-triazole sites strongly combined with columnar [ n ] arene cavities are introduced into the molecular structures of the guest molecules 1 (donor) and the guest molecules 2 (acceptor), orthogonal spirofluorene four-site columnar [ n ] arene host molecules are added into a binary system, and the distance between the donor and the acceptor is greatly shortened under the driving of the interaction of the host and the guest, so that the acceptors can be arranged more closely and orderly; poor solvents are further added into the binary system, the structure of the prepared supramolecular polymer is further regular, and the energy transfer efficiency is greatly enhanced;

(3) the supramolecular polymer is excited by the excitation wavelength of the donor, only the guest molecule 1 (donor) is excited and energy is transferred to the guest molecule 2 (acceptor), and the fluorescence emission and the color of the guest molecule 2 (acceptor) are finally embodied.

According to the preparation method provided by the invention, host molecules, guest molecules 1 (donor) and guest molecules 2 (acceptor) based on spirofluorene four-site column [ n ] arene are dissolved in an organic solvent, water or a mixed solvent to form the supermolecule self-assembly polymer based on host-guest interaction.

Under the synergistic action of a host molecule and a poor solvent, the guest molecule 1 (donor) and the guest molecule 2 (acceptor) which are mutually matched in energy are orderly and tightly arranged, the distance between the host molecule and the poor solvent is greatly shortened, and the energy can be efficiently transferred from the guest molecule 1 (donor) to the guest molecule 2 (acceptor) through an antenna effect and a Fluorescence Resonance Energy Transfer (FRET) mechanism, so that the fluorescence intensity of the three-dimensional supramolecular polymer formed by the host molecule 1 (donor) and the guest molecule 2 (acceptor) with the same concentration is greatly improved.

Compared with the prior art, the invention has the following advantages and effects:

(1) the three-dimensional supramolecular polymer based on spirofluorene four-site column [ n ] arene is formed by self-assembling orthogonal host molecules and two types of guest molecules through interaction of a host and a guest, wherein the host molecular structure adopts an orthogonal spirofluorene structure, so that a powerful support is provided for forming the three-dimensional supramolecular polymer, the column [ n ] arene structure is introduced as a binding site, and cyano-triazole structures tightly combined with the column arene are introduced into the guest molecules, so that the formed supramolecular polymer structure is more compact and regular, the fluorescence resonance energy transfer efficiency is improved, and the process of transferring energy from a donor to the guest is more efficient;

(2) according to the preparation method provided by the invention, a molecular structure of a guest molecule 1 (donor) contains a tetraphenylethylene group with a classic aggregation-induced fluorescence enhancement effect, and excellent fluorescence emission is still shown in an aggregation state, so that an aggregation-induced fluorescence quenching phenomenon is avoided;

(3) the preparation method provided by the invention has the advantages that the energy of the donor and the acceptor are mutually matched, and different from other simple binary systems of the donor and the acceptor, the addition of the host molecule in the supramolecular polymer provided by the invention greatly shortens the distance between the guest molecule 1 (donor) and the guest molecule 2 (acceptor), and can obtain more excellent energy transfer efficiency.

Drawings

FIG. 1 shows the UV absorption spectrum and fluorescence emission spectrum of a host molecule, a guest molecule 1 (donor) and a guest molecule 2 (acceptor) in a tetrahydrofuran solution according to example 1 of the present invention;

FIG. 2 shows fluorescence emission spectra of three-dimensional supramolecular polymers based on spirofluorene four-site column [ n ] arene and prepared in example 3 under the excitation of 335nm and 490nm respectively, and fluorescence emission spectra of polymers prepared with host molecule and guest molecule 1 (donor) ratio of 100:100 under the excitation of 335 nm;

FIG. 3 shows fluorescence emission spectra of three-dimensional supramolecular polymers based on spirofluorene four-site column [ n ] arene and prepared in example 4 under the excitation of 335nm and 490nm respectively, and fluorescence emission spectra of polymers prepared with host molecule and guest molecule 1 (donor) ratio of 50:150 under the excitation of 335 nm.

Detailed Description

The following examples are presented to further illustrate the practice of the invention, but the practice and protection of the invention is not limited thereto. It is noted that the processes described below, if not specifically described in detail, are all realizable or understandable by those skilled in the art with reference to the prior art. The reagents or apparatus used are not indicated to the manufacturer, and are considered to be conventional products available by commercial purchase.