CN-118724797-B - Terpyridyl zinc complex and preparation method and application thereof

Abstract

The invention discloses a terpyridyl zinc complex, a preparation method and application thereof. The terpyridine zinc complex takes transition metal zinc as a central metal ion, terpyridine is taken as a polydentate ligand, can emit red light and near infrared light through the excitation of ultraviolet visible light in an aggregation state, can be used as a luminescent material, can generate active oxygen substances such as singlet oxygen, hydroxyl free radicals and the like under the condition of sunlight irradiation, shows better photosensitivity, and can be used as a photosensitizer.

Inventors

• LIU DIE
• FU FAN
• WANG PINGSHAN

Assignees

• 中南大学

Dates

Publication Date

20260512

Application Date

20230331

Claims (10)

1. 1. A terpyridyl zinc complex is characterized by having a structure of formula 1: Formula 1; Wherein, the X is a balancing anion; r 1 is ; R 2 has the following structural units: ; y is an oxygen atom or a sulfur atom; r 3 is a C 1 ~C 5 alkyl group or a hydrogen atom.
2. 2. A zinc terpyridyl complex according to claim 1, characterized in that: X is PF 6 - ; r 3 is methyl.
3. 3. A preparation method of a terpyridyl zinc complex as claimed in claim 1 or 2, which is characterized by comprising the following steps: 1) 2-bromo-6-acetylpyridine, aldehyde compound with a structure shown in formula 2 and ammonia water are subjected to Michael addition-ring closure reaction to obtain dibromo terpyridine compound with a structure shown in formula 3; 2) Coupling reaction is carried out on the dibromo terpyridine compound and the boric acid compound shown in the formula 4 to obtain a terpyridine ligand with the structure shown in the formula 5; 3) After coordination reaction is carried out on terpyridine ligand and zinc salt, anion replacement reaction is carried out, thus obtaining the terpyridine ligand; ; Wherein, the R 1 is ; R 2 has the following structural units: ; y is an oxygen atom or a sulfur atom; r 3 is a C 1 ~C 5 alkyl group or a hydrogen atom.
4. 4. The method for preparing a terpyridine zinc complex according to claim 3, wherein the 2-bromo-6-acetylpyridine and the aldehyde compound with the structure of formula 2 undergo Michael addition reaction in the presence of alkali, and then ammonia water is added for ring closure reaction.
5. 5. The method for preparing the terpyridyl zinc complex according to claim 4, which is characterized in that: the Michael addition reaction is carried out for 6-10 hours at room temperature.
6. 6. The method for preparing the terpyridyl zinc complex according to claim 4, which is characterized in that: The condition of the ring-closure reaction is that the reaction is carried out for 16-32 hours at the temperature of 70-90 ℃.
7. 7. A process for preparing a zinc terpyridine complex according to claim 3, wherein the dibromo terpyridine compound and the boric acid compound of formula 4 are subjected to coupling reaction under the catalysis of tetrakis (triphenylphosphine) palladium (0) in the presence of alkali.
8. 8. The method for preparing a terpyridyl zinc complex according to claim 7, wherein the coupling reaction is carried out at a temperature of 75-85 ℃ for 30-60 hours.
9. 9. The method for preparing a terpyridyl zinc complex according to claim 3, wherein the condition of the coordination reaction is that the reaction is carried out for 18-32 hours at a temperature of 60-70 ℃.
10. 10. The use of a zinc terpyridyl complex according to claim 1 or 2 for the preparation of photosensitizers or as luminescent materials for luminescent devices.

Description

Terpyridyl zinc complex and preparation method and application thereof Technical Field The invention relates to a zinc complex, in particular to a terpyridyl zinc complex, a synthesis method thereof and application thereof as a photosensitizer or a luminescent material, and belongs to the field of optical materials. Background The photosensitive material with triplet state can generate active oxygen, so that the photosensitive material has wide application in photodynamic therapy, cell imaging, antibiosis, luminescent devices, encryption materials and the like. Normal organic light emitting materials are difficult to achieve triplet emission because intersystem crossing of such materials from the singlet state to the triplet excited state is difficult to achieve. A common approach to achieve triplet emission is to enhance intersystem crossing by introducing heavy atoms or achieving n-pi to increase spin-rail coupling. In addition, the front line orbit separation can be realized, so that the energy difference of exciting the triplet state and the singlet state is reduced, and intersystem crossing is easier. In the conventional metal-organic light emitting materials, most materials use noble metals such as platinum, gold, iridium and the like as the coordination metal ,(Mitra K,Lyons C E,Hartman M C T.A Platinum(II)Complex of Heptamethine Cyanine for Photoenhanced Cytotoxicity and Cellular Imaging in Near-IR Light[J].Angew Chem Int Ed Engl,2018,57(32):10263-10267), because the materials overcome forbidden transition coupling of triplet excitons through strong spin orbitals to promote phosphorescence generation, but the materials have the problems of high cost, environmental pollution and the like. Meanwhile, if the complex formed by the metal is used for photodynamic therapy or cell imaging, the problem of poor solubility is also faced. Therefore, the simple and low-cost synthesis of non-noble metals as photosensitizers or luminescent materials of coordination cores is of great significance. Disclosure of Invention In order to solve the technical problems in the prior art, the first aim of the invention is to provide a terpyridyl zinc complex which has aggregation-induced emission characteristic, can emit red light under ultraviolet excitation and can generate active oxygen substances such as singlet oxygen, hydroxyl free radicals and the like under sunlight. A second object of the present invention is to provide a process for preparing a zinc terpyridyl complex which is simple in operation and steps and low in cost. The third object of the present invention is to provide the application of the terpyridyl zinc complex as a photosensitizer or a luminescent material, wherein the terpyridyl zinc complex can emit 620nm red fluorescence under the excitation of ultraviolet visible light, has the characteristic of aggregation-induced luminescence in a solution, can generate active oxygen substances in a high aggregation state in the solution under the irradiation of sunlight wave bands, and can be widely applied as a photosensitizer or a luminescent material. In order to achieve the technical purpose, the invention provides a terpyridyl zinc complex, which has a structure shown in a formula 1: Wherein, the X is a balancing anion; R 1 is an azacyclic unit, a diazacyclic unit, a benzoazacyclic unit or a benzodiazacyclic unit, R 2 has the following structural unit: Y is a heteroatom; R 3 is a C 1～C5 alkyl group or a hydrogen atom. The terpyridine zinc complex of the invention takes transition metal zinc as a central metal ion, terpyridine compounds as polydentate ligands, and terpyridine compounds can form stable terpyridine zinc complex with octahedral structure with zinc ions. The terpyridine ligand of the terpyridine zinc complex is introduced with a triphenylamine group and an azacyclic group which have higher electron donating ability, the terpyridine has strong electron withdrawing ability, and the strong electron donating ability of the triphenylamine group and the azacyclic group is matched to further enhance the push-pull effect and the special charge transfer effect of electrons, so that the terpyridine zinc complex can emit red light under ultraviolet excitation, the triphenylamine group endows the terpyridine zinc complex with aggregation-induced emission characteristic based on the rotatable characteristic, the terpyridine zinc complex has red light emission in the aggregation state of a solution system, and meanwhile, under the condition of sunlight irradiation, the terpyridine zinc complex can generate active oxygen substances such as singlet oxygen, hydroxyl free radicals and the like, and the terpyridine zinc complex has better photosensitivity. As a preferred embodiment, the terpyridyl zinc complex of formula 1 wherein X is PF 6-,R1 isY is oxygen atom, sulfur or nitrogen atom, and R 3 is methyl. R 1 is preferably a nitrogen-containing heterocyclic unit such as a pyridine unit, pyrazine unit, pyrimidin