The porphyrin-like macrocycles and their metal complexes are s novel family of photoresponsive molecules.The properties of the excited states,both singlet and triplet are investigated by the stationary and transient p...The porphyrin-like macrocycles and their metal complexes are s novel family of photoresponsive molecules.The properties of the excited states,both singlet and triplet are investigated by the stationary and transient processes.展开更多
This paper presents the synthesis and structural characterization of asymmetric tripyrrane-containing macrocycle.This macrocycle could be oxidized to the methine bridged,22 π-electron aromatic macrocyclic complexes c...This paper presents the synthesis and structural characterization of asymmetric tripyrrane-containing macrocycle.This macrocycle could be oxidized to the methine bridged,22 π-electron aromatic macrocyclic complexes containing cadmium(Ⅱ),samarium (Ⅲ),europium(Ⅲ)and gadolinium(Ⅲ)by treating with corresponding metal chloride in the presence of air Their structures were characterized by spectral methods.展开更多
The research results of the excited-state properties of asymmetric pentaazadentate ex-panded-porphyrins are reported. The results show that the emission spectra appear in the 770-820 nm region in accord with the diffe...The research results of the excited-state properties of asymmetric pentaazadentate ex-panded-porphyrins are reported. The results show that the emission spectra appear in the 770-820 nm region in accord with the different substituents on the benzene ring. The quantum yield of fluorescence is less than 0.02, and the lifetime of the first singlet excited state (S1) is shorter than 1ns. There are excellent linear relationships between the energy of the S1 and the Hammett constants as well as the quantum yield of fluorescence and the electrophilic substituent constants σ+. The energies of the lowest excited triplet state (T1) of the complexes are in the range of 94 -130kJ/mol. The lifetime of T 1 is as long as tens of microseconds. The T1-Tn transient absorption spectra appear in 450-550 nm region. And the quantum yield of title compounds for generating singlet oxygen is as high as 0.9.展开更多
The linear correlations of Hammett constants with the 0-0 transition energies, and the ratios of the oscillator strength are used to probe the conjugation interactions between π-electron of macrocy-cles and metal ion...The linear correlations of Hammett constants with the 0-0 transition energies, and the ratios of the oscillator strength are used to probe the conjugation interactions between π-electron of macrocy-cles and metal ion of complexes with the substituents on m-position of benzene ring for the asymmetric pen-taazadentate porphyrin-like compounds. The absorption and fluorescence spectra appear on λmax> 750 nm and 769 nm near-IR regions respectively. The quantum yields and lifetimes of fluorescence are about 10-2and less than 1 ns respectively. The T1--Tn transient absorption spectra appear on 487-496 nm and thequantum yields for generating singlet oxygen are as high as 0. 86.展开更多
A novel pentaazadentate bismacrocycle was synthesized through an improved procedure of 1:1 Schiff base condensation of diformyltripyrrane with 3, 4, 3', 4'-tetraamino-biphenyl hydrochloride using Pb2+ as templ...A novel pentaazadentate bismacrocycle was synthesized through an improved procedure of 1:1 Schiff base condensation of diformyltripyrrane with 3, 4, 3', 4'-tetraamino-biphenyl hydrochloride using Pb2+ as template ion, in which the condensed byproduct water was removed efficiently to make the yield over 90%. Then the bismacrocyclic ligand reacted with cadmium chloride to Field the title metal complex with molecular weight being 1200.4 by TOF MS and the lambda(max) being 766 nm.展开更多
文摘The porphyrin-like macrocycles and their metal complexes are s novel family of photoresponsive molecules.The properties of the excited states,both singlet and triplet are investigated by the stationary and transient processes.
文摘This paper presents the synthesis and structural characterization of asymmetric tripyrrane-containing macrocycle.This macrocycle could be oxidized to the methine bridged,22 π-electron aromatic macrocyclic complexes containing cadmium(Ⅱ),samarium (Ⅲ),europium(Ⅲ)and gadolinium(Ⅲ)by treating with corresponding metal chloride in the presence of air Their structures were characterized by spectral methods.
基金Project supported by the National Natural Science Foundation of China
文摘The research results of the excited-state properties of asymmetric pentaazadentate ex-panded-porphyrins are reported. The results show that the emission spectra appear in the 770-820 nm region in accord with the different substituents on the benzene ring. The quantum yield of fluorescence is less than 0.02, and the lifetime of the first singlet excited state (S1) is shorter than 1ns. There are excellent linear relationships between the energy of the S1 and the Hammett constants as well as the quantum yield of fluorescence and the electrophilic substituent constants σ+. The energies of the lowest excited triplet state (T1) of the complexes are in the range of 94 -130kJ/mol. The lifetime of T 1 is as long as tens of microseconds. The T1-Tn transient absorption spectra appear in 450-550 nm region. And the quantum yield of title compounds for generating singlet oxygen is as high as 0.9.
基金Project supported by the National Natural Science Foundation of China.
文摘The linear correlations of Hammett constants with the 0-0 transition energies, and the ratios of the oscillator strength are used to probe the conjugation interactions between π-electron of macrocy-cles and metal ion of complexes with the substituents on m-position of benzene ring for the asymmetric pen-taazadentate porphyrin-like compounds. The absorption and fluorescence spectra appear on λmax> 750 nm and 769 nm near-IR regions respectively. The quantum yields and lifetimes of fluorescence are about 10-2and less than 1 ns respectively. The T1--Tn transient absorption spectra appear on 487-496 nm and thequantum yields for generating singlet oxygen are as high as 0. 86.
基金Project (No. 29832030, 2982001) supported by the National Natural Science Foundation of China.
文摘A novel pentaazadentate bismacrocycle was synthesized through an improved procedure of 1:1 Schiff base condensation of diformyltripyrrane with 3, 4, 3', 4'-tetraamino-biphenyl hydrochloride using Pb2+ as template ion, in which the condensed byproduct water was removed efficiently to make the yield over 90%. Then the bismacrocyclic ligand reacted with cadmium chloride to Field the title metal complex with molecular weight being 1200.4 by TOF MS and the lambda(max) being 766 nm.
