Meso Aryl-substituted Porphines: Synthesis, Characterization And Optical Properties Research

A series of substituted porphines were designed and synthesized. The structures ofporphines were confirmed by1H-NMR, MS and Element analysis. Optical properties ofporphines were mearsured and and the structure influence on the optical propertises wereinvestigatd.The data about molecular structures and the electonic energy of porphines werecalculated through molecular simulation. The main contents were sunmmarized as follows:(1)ABC2, A2B2, AB3and A4type substituted porphines were synthesized by Macdonaldmethod and Adler method according their symmetric structure with pyrrole and aldehydes.Target products were confirmed by1H-NMR, MS and Element analysis.The factors such astemperature,substrate concentration and reaction time that had effects on the yield of porphinewere studied.(2)The absorption spectrum and emission spectrum of porphine were obtained by relatedmeasurement. The results showed that: as the numbers of aryl substituent increased, theabsorption maximum showed bathochromic shift. Each aryl could cause about6nm red shiftto the absorption maximum of porphine.As for the fluorescence quanmt yield; it wasinfuenced by substituents and symmetry structure of porphine. For the A2B2type porphine,the fluorescence quanmt yield of5,15,-di(3-hydroxyphenyl)porphine,5,15,-di(3-chlorophenyl)porphine and5,15,-di(3-bromophenyl) porphine were respectively0.15,0.12and0.08. The fluorescence quanmt yield of porphine decreased when the aryl wasbrominated or chlorinated. Symmertrical structures also had influence on the fluorescencequamt yield. Taken the meso-phenyl substituted porphine for exsample: the fluorescencequamt yield of AB3type5-phenylporphine and5,10,15-triphenylporin were0.20and0.19compared to A2B2type5,15-diphenylporphytin and A4type5,10,15,20-tetraphenylporphinewere respectively0.17and0.11.A high fluorescence quamt yield of porphyin owed to anunsymmetrical structure.(3)Two-photon fluorescence properties of porphine were measured by the laser lightsource. The two-photon absoption cross sections for porphines were gained within the rangeof680-800nm laser. The results showed that porphines presented maximum two-photonfluorescence under680nm. The two-photon absorption crosssection sections of5,15,-di(3-bromophenyl) porphine,5,15,-di(3-chlorophenyl)porphine and5,15,-di(3-hydroxyphenyl)porphine were respectively9489GM,6012GM and2459GM.(4)Gausse03software was used to optimixed the structure of porphine with the theory ofDFT/B3LYP(density functional theoty). The energy gaps of porphine between ground stateand different excited states were calculated based on the optimixed structure. When the porphine was substitued by aryl, the energy gap decreased and the absorption maximum ofporphine exhibited red shift. All that identified that aryl substituent act as electron-donor.