Study On Synthesis And Properties Of Novel Porphyrins

In the past decades, synthesis and applications of porphyrins andmetalloporphyrins have received continuous attentions due to their special structuresand properties. Based on works had been done before, this article presented some newstudies on structural modifications of meso-tetraphenylporphyrin (TPP), synthesis ofporphyrin dimers, synthesis of tailed metalloporphyrins and their applications asmolecule catalysts. A series of new porphyrin compounds were synthesized and theirelectrospectra were studied. In addition, the applications of tailed metalloporphyrinswith the structure of axial coordination within molecule as catalysts in oxidationreaction and cyclopropanation reaction were primary studied. The whole article wasdivided into six chapters:Chapter one: The progress on synthesis and structural modifications ofmeso-tetraarylporphyrins, synthesis of oligomeric porphyrins, preparation ofmetalloporphyrins and their applications as molecule catalysts were well reviewed.Chapter two: Using 5-(4-aminophenyl)-10,15,20-triphenylporphyrin as thestarting compound, the classical diazotization of aniline and the resulting reaction ofdiazo salts were applied to porphyrin for the first time, and a series of asymmetriclysubstituted meso-tetraarylporphyrins including 5-(4-chlorophenyl)-10,15,20-triphenylporphyrin, 5-(4-iodinphenyl)-10,15,20-triphenylporphyrin, 5-(4-cyanophenyl)-10,15,20-triphenylporphyrin, 5-(4-bisphenyl)-10,15,20-triphenylporphyrin and 5-(4-hydroxylphenyl)-10,15,20-triphenylporphyrin were synthesized.Chapter three: With chlorosulfonic acid, sodium chloride and formaldehyde as thechloromethylation reagent, regiospecific aryl chloromethylation of TPP was realizedin controlled mauner after appropriate organic solvent had been used. A series ofderivatives of meso-tetraphenylporphyrin with different number of chloromethylgroups having been substituted at para positions of phenyls were synthesized. Furtherderivatization of 5-(4-chloromethylphenyl)-10,15,20-triphenylporphyrin was subsequently proceeded and 5-(4-formylphenyl)-10,15,20-triphenylporphyrin and5-(4-hydroxylmethylphenyl)-10,15,20-triphenylporphyrin were obtained.Chapter four: This chapter focused on the synthesis of porphyrin dimers, and itcontained two parts: Firstly, employing a 5-(4-chloromethylphenyl)-10,15,20-triphenylporphyrin-derived Wittig reagent, four stilbene-linked porphyrin dimers in cis formwere prepared by Wittig reaction, and their absorption and emission spectra were alsostudied; Secondly, five diaryl ether-linked porphyrin dimers were synthesized viaUllmann coupling reaction and their absorption and emission spectra were studied.Chapter five: After six steps including Vilsmeier reaction, reduction reaction andcoupling reaction etc, a novelβ-tailed iron porphyrin was prepared with TPP as thestarting material. Its absorption spectrum indicated that the tail end imidazole groupcould well coordinate with the central iron.Chapter six: The synthesizedβ-tailed iron and cobalt porphyrins were applied ascatalysts to the oxidation of cyclohexane and cyclopropanation of styrene separately.Compared to iron porphyrin without tailed group, the tailed iron porphyrin showedhigher catalysis activity, furthermore, it could help to improve the selectivity of theoxidation products. The result of cyclopropanation of styrene indicated that tailedcobalt porphyrin could improve the selectivity of products obviously despite itscatalysis activity was depressed.