Synthesis And Photoconductivities Of Novel Substituted Porphyrins At Meso And β Position

In this paper, a series of novel meso-substituted azo-porphryins and a series of novelβ-substituted chlorins and porphyrins derivatives were designed and synthesized. Bilayer devices were prepared by using new porphyrins and chlorins as charge-generation layer separately. And their photoconductivities were measured and discussed. The synthesis of imide substituted porphyrin at meso andβpositions were also studied.Nine novel covalently-connected bi-, tri- and tetra- substituted azo-porphyrin conjugates were prepared by diazo-coupling reaction from aminophenylporphyrins. Two symmetrical porphyrins of azo-porphyrins were also synthesized by Alder method of pyrrole and azobenzaldehydes which were perpared from p-amido-benzaldehydes by diazo-coupling. The new azo-porphyrins reacted with metal salt (Zn) and nine new azo-metalloporphyrins were obtained. The new compounds were characterized by 1H NMR, IR, MS and UV-Vis spectra. The azo-hydrazone tautomerism of 2-hydroxy-azonaphthyl-phenylporphyrins 3a-c were discussed by 1H NMR and UV-Vis. The UV-Vis and fluorescence spectra of new azo-porphyrins were studied. The absorption spectra of new azo-porphyrins exhibited the typical bands (Azo, Soret, Q). And the intermolecular fluorescence quenching of 2-hydroxy-azonaphthyl-phenylporphyrins 3a-c was detected in the fluorescence emission spectra.Bilayer devices were prepared by using the azo-porphyrins as charge-generation layer separately, and their photoconductivities were measured and discussed. The experimental results showed that the photoconductivities of azo-porphyrins were improved comparing with tetraphenylporphyrin (TPP). And the sensitivity of 5,10,15, 20-tetra(4-(p-hydroxy-azophenyl)-phenyl) porphyrin was 1.8 lx·s.Seven novel H, Cl, CH3, OCH3 substituted isoxazole-fused chlorins and eight isoxazole-fused bacteriochlorins were perpared by 1,3-dipolar cycloaddition reactions of nitrile oxides with porphyrins. The yields were between 4% and 54%. The two new isoxazole-fused chlorins were synthesized by 1,3-dipolar cycloaddition reactions from hydroxymoyl chloride and porphyrins. And the yields were 10% and 11%. The new compounds were characterized by 1H NMR, 13C NMR, IR, MS, HRMS and UV-Vis spectra. The chlorins and bacteriochlorins had strong absorption in the red region ofthe visible region near or above 650 nm. However they didn't show photoconductivities.2-Aldehyde tetra-(p-methyoxyphenyl)-porphyrin nickel (Ⅱ) as 1, 3-dipolar reacted with 1,4-benzoquinone and N-phenyl-maleimide to generate three newβsubstituted porphyrins compounds. Their yields were 25%, 61% and 35% respectively. The C=O of Isatin underwent regioselective 1,3-dipolar cycloaddition reactions with porphyrin azomethine ylides derived from Ni (II)β-formyl-meso-tetraphenyl porphyrin in the presence of N-methylglycine to afford novel spiro porphyrin derivatives. The yields were 13% and 41% respectively. The structure of new compounds were confirmed by 1H NMR, IR, MS and UV-Vis spectra. The symmetrical imido-subtituted porphyrin at meso position was perpared through two different routes. The yields were 37% and 49%. The imido-substituted porphyrin derivative atβposition was gained by 1,3-dipolar cycloaddition reaction from porphyrin and hydroxymoyl chloride. The new compounds were characterized by 1H NMR, 13C NMR, IR, MS and UV-Vis spectra.