Design,Synthesis And Properties Of Nitrogen-Bridged And Amino-Modified Porphyrin Arrays

Porphyrinoids are organic functional molecules with large?-conjugated systems,which have potential applications in optoelectronic devices,sensors and photodynamic therapy(PDT).The structure of the porphyrin array can be modified to artificially regulate the performance of the molecule.We synthesized a series of nitrogen-bridged porphyrin arrays by nucleophilic substitution reaction or Buchwald-Hartwig coupling reaction of meso-bromoporphyrin and meso-aminoporphyrin.The detailed work content of this paper has the following aspects:(1)Hexaphenylbenzene was synthesized by Pd(II)catalyzed alkyne[2+2+2]trimerization reaction of diphenylacetylene,the following hexaphenylbenzenereactwithBr₂togive1,2,3,4,5,6-hexakis(4-bromophenyl)benzene.wesynthesized meso-bromoporphyrin,meso-borylporphyrin,and meso-aminoporphyrin through bromination,boronation and amination respectively.These compounds have been characterized by ¹H MNR spectroscopy.(2)The porphyrin hexamer was synthesized by Suzuki-Miyaura cross-coupling reaction of 1,2,3,4,5,6-hexakis(4-bromophenyl)benzene with meso-borylporphyrin.meso-bromoporphyrin hexamers and meso-chloroporphyrin hexamers were synthesized by halogenation reaction from 1,2,3,4,5,6-hexakis(4-bromophenyl)benzene and NBS/NCS in quantitative.Finally,the peripherally modified hexamer was synthesized by nucleophilic substitution of meso-chloroporphyrin hexamers and trichloroaniline.The benzene-centered N-bridged porphyrin 12-mer was synthesized by Buchwald-Hartwig coupling reaction of meso-bromoporphyrin hexamers with meso-aminoporphyrin.These compounds were characterized by ¹H MNR and MALDI-TOF MS spectroscopy.Some compounds were tested for photophysical properties by UV-visible absorption spectroscopy.(3)The L-shaped N-bridged porphyrin trimer and linear N-bridged porphyrin trimer were obtained by Buchwald-Hartwig coupling reaction of meso-aminoporphyrin and 5,10-dibromoporphyrin or5,15-dibromoporphyrin,respectively.L-shaped NH-bridged and linear NH-bridged porphyrin trimer were achieved by reduction of L-shaped N-bridged porphyrin trimer and linear NH-bridged porphyrin trimer,respectively.These compounds were characterized by ¹H MNR and MALDI-TOF MS spectroscopy.The structure of some compounds were determined by X-ray crystal diffraction,some compounds were tested for photophysical properties by UV-visible absorption spectroscopy.