CN111171057A

CN111171057A - A kind of Cu(II) supramolecular complex and preparation method thereof

Info

Publication number: CN111171057A
Application number: CN202010045077.6A
Authority: CN
Inventors: 阮明岳; 杨长琴; 王磊; 魏太保; 林奇
Original assignee: Northwest Normal University
Current assignee: Northwest Normal University
Priority date: 2020-01-16
Filing date: 2020-01-16
Publication date: 2020-05-19

Abstract

本发明提供了一种Cu（Ⅱ）超分子配合物及其制备方法，是以3,5‑二硝基苯甲酸、咪唑和乙酸铜为原料，以甲醇水溶液为溶剂，用三乙胺调节pH至8~9，于80~100℃下反应20~24h，冷却、洗涤、干燥，得到蓝色长条状晶体，即为Cu（Ⅱ）超分子配合物。该Cu（Ⅱ）超分子配合物的化学式为Cu（DNBC）（Im），其中DNBC为3,5‑二硝基苯甲酸，Im为咪唑，晶系为单斜晶系，空间群为P2₁ /c，晶格常数为a=5.5698Å，b=10.0204Å，c=21.2903Å，V=1181.4Å³，Z=2。通过水热法制备得到Cu（Ⅱ）超分子配合物，制备方法简单，晶体生长速度较快，应力小，均匀性好且具有较完整的外形，在分子识别、包结催化、吸附分离及储氢材料等方面都具有重要的潜在应用前景。The invention provides a Cu(II) supramolecular complex and a preparation method thereof, which use 3,5-dinitrobenzoic acid, imidazole and copper acetate as raw materials, use methanol aqueous solution as solvent, and adjust pH with triethylamine To 8~9, react at 80~100℃ for 20~24h, cool, wash and dry to obtain blue long strip crystals, which are Cu(II) supramolecular complexes. The chemical formula of the Cu(II) supramolecular complex is Cu(DNBC)(Im), wherein DNBC is 3,5-dinitrobenzoic acid, Im is imidazole, the crystal system is monoclinic, and the space group is P 2 ₁ /c, the lattice constants are a = 5.5698Å, b = 10.0204Å, c = 21.2903Å, V=1181.4Å ³ , Z=2. The Cu(II) supramolecular complexes were prepared by the hydrothermal method. The preparation method is simple, the crystal growth rate is fast, the stress is small, the uniformity is good and the shape is relatively complete. Hydrogen materials and other aspects have important potential application prospects.

Description

Cu (II) supermolecule complex and preparation method thereof

Technical Field

The invention relates to a Cu (II) supramolecular complex and a preparation method thereof, belonging to the field of material chemistry.

Background

In recent years, the rapid development of nano materials and coordination chemistry injects infinite vitality into ancient inorganic chemistry, the supermolecular complex has both inorganic and organic components, and by designing appropriate organic polydentate ligands and metal salt to react and adjusting different influence factors, the supermolecular complex with different novel structures is obtained, which is the leading-edge and hot-spot subject of the fields of current chemistry, physics, materials, medicine, biology and the like. The coordination supermolecule with a novel structure is designed and constructed by utilizing the principles of molecular recognition and molecular assembly, a supermolecule system with a specific biological function is researched and constructed, the method has important significance for revealing life phenomena and processes, a new application system is provided for material science, and a new thought and direction are provided for multidisciplinary cross research of physics and chemistry and the like.

The carboxylic acid ligand is a kind of ligand commonly used for constructing coordination polymers, and carboxyl is widely applied to the design and synthesis of the complex by flexible and various coordination modes (monodentate, bidentate, bridging and the like). The negative electrical properties of the carboxyl groups themselves compensate for the positive electrical properties of the cations, thereby slowing down the counter ion effect. In addition, some weak interactions between molecules, such as hydrogen bonds and pi-pi stacking, further enhance the stability of the structure. Imidazole not only has strong coordination ability, but also is a donor of hydrogen bond, so that imidazole is widely applied to preparation of transition metal coordination polymers. Particularly, the complex formed by the imidazole structure-containing ligand and the transition metal ions has excellent physical and chemical properties and has potential application value in the fields of chemistry, biology, materials and the like. Therefore, 3, 5-dinitrobenzoic acid and imidazole are taken as ligands to react with transition metal ions Cu (II) to prepare the Cu (II) supermolecule complex.

Disclosure of Invention

The invention aims to provide a Cu (II) supramolecular complex and a preparation method thereof;

preparation of mono-Cu (II) supermolecule complex

The preparation method of the Cu (II) supramolecular complex comprises the steps of taking 3, 5-dinitrobenzoic acid, imidazole and copper acetate as raw materials, taking a methanol water solution as a solvent, adjusting the pH value to 8-9 by using triethylamine, reacting for 20-24 hours at 80-100 ℃, cooling, washing and drying to obtain blue strip crystals, namely the Cu (II) supramolecular complex. Wherein the molar ratio of the 3, 5-dinitrobenzoic acid to the imidazole to the copper acetate is 1:1: 1-2: 2: 1; in the methanol water solution, the volume percentage of methanol is 50-60%.

Structure of di, Cu (II) supermolecule complex

FIG. 1 is a single crystal diagram of a Cu (II) supramolecular complex, which is seen as a large, regular blue, elongated crystal.

The prepared Cu (II) supramolecular complex is subjected to an X-ray diffraction test to obtain an X-ray diffraction pattern (figure 2) of the Cu (II) supramolecular complex, and four strong peak positions of the pattern are obvious, (011) (2 theta = 9.758), (013) (2 theta = 15.346), (120) (2 theta = 23.932) and (-1-31) (2 theta = 31.301), which indicates that the crystallinity of the synthesized sample is good.

The X-ray diffraction data were refined using Olex2 software to obtain a structural unit map of the Cu (ii) supramolecular complex (fig. 3). As shown in FIG. 3, the chemical formula of the Cu (II) supramolecular complex is Cu (DNBC) (Im), wherein DNBC is 3, 5-dinitrobenzoic acid, Im is imidazole, the crystal system is monoclinic system, and the space group isP2₁ /c，Lattice constanta=5.5698（2）Å，b=10.0204 （3）Å，c=21.2903（6）Å，V=1181.4(7)Å³Å Z Å = Å 2 Å, Å the Å central Å metal Å copper Å atom Å is Å bidentate Å and Å is Å respectively Å coordinated Å with Å 1 Å N Å (Å from Å imidazole Å ligands Å) Å and Å two Å carboxyl Å groups Å O Å (Å from Å 3 Å, Å 5 Å - Å dinitrobenzoic Å acid Å ligands Å) Å, Å the Å average Å distance Å between Å Cu Å - Å O Å is Å 1.939 Å, Å the Å average Å distance Å between Å Cu Å - Å N Å is Å 1.943 Å A Å, Å the Å average Å distances Å are Å almost Å equal Å, Å the Å coordination Å capability Å of Å N Å and Å O Å is Å equivalent Å, Å the Å bond Å angle Å formed Å between Å three Å atoms Å of Å N Å - Å Cu Å - Å O Å is Å 90.823 Å degrees Å, Å and Å the Å complex Å molecules Å are Å connected Å into Å a Å three Å - Å dimensional Å net Å structure Å by Å hydrogen Å bond Å, Å van Å der Å Waals Å force Å, Å spatial Å position Å matching Å, Å electrostatic Å interaction Å (Å ionic Å interaction Å, Å hydrogen Å bond Å) Å and Å stacking Å interaction Å (Å hydrophobic Å interaction Å, Å aromatic Å ring Å stacking Å) Å and Å the Å like Å on Å the Å basis Å of Å non Å - Å covalent Å bond Å weak Å interaction Å. Å

In conclusion, the Cu (II) supramolecular complex is prepared by taking 3, 5-dinitrobenzoic acid, imidazole and copper acetate as raw materials and utilizing a hydrothermal method, and the Cu (II) supramolecular complex is simple in preparation method, high in crystal growth speed, small in stress, good in uniformity and complete in appearance. The molecules of the complex are connected into a three-dimensional net supramolecular structure by hydrogen bonds, van der waals force, space position matching, electrostatic interaction (ionic interaction and hydrogen bonds), stacking interaction (hydrophobic interaction and aromatic ring stacking) and the like on the basis of non-covalent bond weak interaction. The Cu (II) supermolecule complex has important potential application prospect in the aspects of molecular recognition, inclusion catalysis, adsorption separation, hydrogen storage materials and the like.

Drawings

FIG. 1 is a single crystal diagram of a Cu (II) supramolecular complex;

FIG. 2 is an X-ray diffraction pattern of a Cu (II) supramolecular complex;

FIG. 3 is a diagram of structural units of a Cu (II) supramolecular complex.

Detailed Description

Example 1

3, 5-dinitrobenzoic acid (0.2143 g, 1 mmol) having a purity of 99.0%, imidazole (0.0688g, 1 mmol) having a purity of 99.0%, and copper acetate (0.1834 g, 1 mmol) having a purity of 99.0% were weighed, and 10mL of an aqueous methanol solution (V)_(EtOH):V_{Water (W)}1: 1), stirring and mixing uniformly, slowly adjusting to 8 with triethylamine, transferring the solution into a reaction kettle with a polytetrafluoroethylene lining, sealing, screwing, placing the reaction kettle in an electronic temperature-controlled oven, reacting for 24 hours at 100 ℃, setting the heating rate to be 5 ℃/min-7 ℃/min, the cooling rate to be 1 ℃/h-5 ℃/h, washing the crystal with water when cooling to room temperature, and drying to obtain a larger blue strip crystal with a regular shape, namely the Cu (II) supermolecule complex.

Example 2

3, 5-dinitrobenzoic acid (0.4285 g, 2 mmol) having a purity of 99.0%, imidazole (0.0688g, 1 mmol) having a purity of 99.0%, and copper acetate (0.1834 g, 1 mmol) having a purity of 99.0% were weighed, and 10mL of an aqueous methanol solution (V)_(EtOH):V_{Water (W)}=1: 1), stirring and mixing uniformly, slowly adjusting to 9 by using triethylamine, transferring the solution to a reaction kettle with a polytetrafluoroethylene lining, sealing, screwing, and performingAnd (3) placing the reaction kettle in an electronic temperature-controlled oven, reacting for 24 hours at 80 ℃, setting the heating rate to be 5-7 ℃/min, setting the cooling rate to be 1-5 ℃/h, washing the crystal with water when the temperature is reduced to room temperature, and drying to obtain a larger blue strip crystal with a regular shape, namely the Cu (II) supermolecule complex.

Example 3

3, 5-dinitrobenzoic acid (0.4285 g, 2 mmol) having a purity of 99.0%, imidazole (0.1376g, 2 mmol) having a purity of 99.0%, and copper acetate (0.1834 g, 1 mmol) having a purity of 99.0% were weighed, and 10mL of an aqueous methanol solution (V)_(EtOH):V_{Water (W)}And =1: 1), stirring and mixing uniformly, slowly adjusting the solution to 8 by triethylamine, transferring the solution into a reaction kettle with a polytetrafluoroethylene lining, sealing, screwing, placing the reaction kettle in an electronic temperature-controlled oven, reacting for 20 hours at 100 ℃, setting the heating rate to be 5 ℃/min-7 ℃/min, the cooling rate to be 1 ℃/h-5 ℃/h, washing the crystal by water when the temperature is reduced to room temperature, and drying to obtain a larger blue strip crystal with a regular shape, namely the Cu (II) supermolecule complex.

The structural units of the Cu (II) supramolecular complexes prepared in examples 1-3 are shown in FIG. 3, and the Cu (II) supramolecular complex has a chemical formula of Cu (DNBC) (Im), wherein DNBC is 3, 5-dinitrobenzoic acid, Im is imidazole, the crystal system is monoclinic, and the space group isP2₁ /c，Lattice constanta=5.5698（2）Å，b=10.0204 （3）Å，c=21.2903（6）Å，V=1181.4(7)Å³Z = 2; the central metallic copper atom is bidentate, coordinating with 1N (from imidazole ligand) and two carboxy groups O (from 3, 5-dinitrobenzoic acid ligand) respectively.

Claims

1. A preparation method of a Cu (II) supramolecular complex is characterized by taking 3, 5-dinitrobenzoic acid, imidazole and copper acetate as raw materials, taking a methanol water solution as a solvent, adjusting the pH value to 8-9 by triethylamine, reacting for 20-24 hours at 80-100 ℃, cooling, washing and drying to obtain blue strip crystals, namely the Cu (II) supramolecular complex.

2. A method for preparing Cu (ii) supramolecular complexes as claimed in claim 1, characterized in that: the molar ratio of the 3, 5-dinitrobenzoic acid to the imidazole to the copper acetate is 1:1: 1-2: 2: 1.

3. A method for preparing Cu (ii) supramolecular complexes as claimed in claim 1, characterized in that: in the methanol water solution, the volume percentage of methanol is 50-60%.

4. A Cu (II) supramolecular complex prepared by the method of claim 1, having a chemical formula of Cu (DNBC) (Im), wherein DNBC is 3, 5-dinitrobenzoic acid, Im is imidazole, the crystal system is monoclinic, and the space group isP2₁ /c，Lattice constant ofa=5.5698Å，b=10.0204 Å，c=21.2903Å，V=1181.4Å³，Z=2。