Synthesis Of Meso-Azaaromatics Substituted Porphyrins And Study On Their Spectrum Properties

Porphyrin has a stable molecule structure for its macrocyclic conjugated properties, is a class of classic red luminescent material. The advantages of good fluorescence emission and ease of s ynthesis and modification make porphyrins widel y used in organic electroluminescent material field. At present, there are still many problems for the porphyrins used as a light emitting material, such as weak solid fluorescence, impure light color, low fluorescence quantum yield and intermolecular fluorescence quenching, which limits the applications of the porphyrins as the red light material that is the key to display organic full color. Electron-rich imidazole and carbazole with their derivatives are excellent blue luminescent materials as N-heteroaromatic ring species,and possess high fluorescence quantum yield. They can make up the defects for porph yrin light-emitting material, and their fluorescence emission peak has good overlapping with UV absorption peak of the porph yrin. Carbazole and imidazole with their derivatives could be the energy donor group and transfer energy to porphyrin acceptor group under relativel y specific conditions. It would be ver y important to prevent aggregation of the porph yrin molecules and improve luminous efficiency, if N-heteroaromatic ring with special functions was connected to the porphyrin ring meso-position carbon through a certain way. In this text, we designed and synthesized several imidazole and carbazole substituted porphyrins in different ways, and studied their spectral properties mainly. The main contents of this thesis are as follows:1. The research progress of the porph yrin, imidazole and carbazole compounds in the field of synthesis and light-emitting material were briefl y introduced, and described the research situation of imidazole and carbazole porph yrins.2. According to lindsey method,One-pot synthesized 5,15-diphenylporph yrin and 5,10,15-triphen ylporphyrin. Meanwhile, synthesized two brominated products, 5,15-diphen yl porph yrin and 5,10,15-triphenylporph yrin, and one single-form ylated substituted meso-porphyrin intermediate product. All the porphyrins were characterized b y nuclear magnetic resonance, mass spectrum and elemental anal ysis. We discussed and improved the s ynthetic method.3. We designed and s ynthesized eight differcent porph yrin compounds: two kinds of mono- and di-substituted imidazole C-N conjugated diphen ylporphyrins, two kinds of mono- and di-substituted carbazole C-N conjugated diphen ylporphyrins, two kinds of imidazole and carbazole substituted C-N conjugated triphen ylporphyrins, two kinds of imidazole derivatives mono-substituted C-C conjugated diphen yl porphyrins. All the compounds were characterized by nuclear magnetic resonance, mass spectrum and elemental anal ysis. We discussed and improved the synthetic method.4. We studied the spectral properties of these porphyrins which were synthesized in this paper, and obtained their fluorescence quantum yields. We discovered that the UV absorption spectrum of all the N-heteroaromatic ring substituted porph yrins showed better performance UV absorption redshift than the parent porphyrin 5,10-diphenylporph yrin and 5,10,15-triphen ylporphyrin. Compared with the tetraphen ylporphyrin,-N- substituted carbazole porphyrin showed better performance fluorescence emission redshift. The fluorescence quantum yields of the-C- substituted phenanthroimidazole and bibenzimidazole porphyrins were improved..5. Gaussian 03 software was used to optimize the structure of porphyrin with RHF theor y. The molecular structure date and molecular orbital energy were obtained. Combined with molecular orbital theor y simulated porph yrins molecular structure to give porph yrin molecule junction parameters and molecular orbital energy level. Based on their structural characteristics, we anal yzed and explained their spectroscopic properties. According to the structural characteristics, a reasonable anal ysis and interpretation was used to explain spectra performance, the rules between energy gaps and the redshift of the maximum UV absorption peak and fluorescence emission peak were consistent.