Thermogravimetry was used to study the non-isothermal decomposition kinetics and the stability of porphyrin copper-sodium from ephedra. The kinetic equation for the second step can be expressed as . The kinetic compe...Thermogravimetry was used to study the non-isothermal decomposition kinetics and the stability of porphyrin copper-sodium from ephedra. The kinetic equation for the second step can be expressed as . The kinetic compensation effect is found to be: InA=0. 2468E a ?8. 0513.Ea is 206. 61 kJ/mol. The results show that porphyrin copper-sodium has a high activation energy and good stability.展开更多
Aggregation behavior of 5,10,15-tris(pentafluorophenyl)corrole (F15TPC), 5,10,15,20-tetra(pentafluoroph-enyl)porphyrin (F20TPP), and their copper complexes in DCM solution were investigated by using UV-Vis spectro-sco...Aggregation behavior of 5,10,15-tris(pentafluorophenyl)corrole (F15TPC), 5,10,15,20-tetra(pentafluoroph-enyl)porphyrin (F20TPP), and their copper complexes in DCM solution were investigated by using UV-Vis spectro-scopic method. F20TPP and F20TPPCu exhibited strong π-π stacking interactions in DCM, and the intermolecular dimerization constants turned out to be 1.82 × 103 and 17.2 × 103 L·mol-1 respectively. However, extinction coefficients of F15TPC and F15TPCCu at soret band remained unchanged with increasing in their concentrations from 1.0 to 40.0 μmol·L-1, indicating they remained monomeric in DCM solution. Based on DFT calculation and the π-π stacking geometries observed in crystal structures of metal octaethylcorrole complexes, destroy of π-π interactions in F15TPC and F15TPCCu may be understood by the electrostatic potential surfaces (EPS) features of the molecules and steric repulsions caused by the introducing of three phenyl at the meso- positions of corrole macrocycle.展开更多
文摘Thermogravimetry was used to study the non-isothermal decomposition kinetics and the stability of porphyrin copper-sodium from ephedra. The kinetic equation for the second step can be expressed as . The kinetic compensation effect is found to be: InA=0. 2468E a ?8. 0513.Ea is 206. 61 kJ/mol. The results show that porphyrin copper-sodium has a high activation energy and good stability.
文摘Aggregation behavior of 5,10,15-tris(pentafluorophenyl)corrole (F15TPC), 5,10,15,20-tetra(pentafluoroph-enyl)porphyrin (F20TPP), and their copper complexes in DCM solution were investigated by using UV-Vis spectro-scopic method. F20TPP and F20TPPCu exhibited strong π-π stacking interactions in DCM, and the intermolecular dimerization constants turned out to be 1.82 × 103 and 17.2 × 103 L·mol-1 respectively. However, extinction coefficients of F15TPC and F15TPCCu at soret band remained unchanged with increasing in their concentrations from 1.0 to 40.0 μmol·L-1, indicating they remained monomeric in DCM solution. Based on DFT calculation and the π-π stacking geometries observed in crystal structures of metal octaethylcorrole complexes, destroy of π-π interactions in F15TPC and F15TPCCu may be understood by the electrostatic potential surfaces (EPS) features of the molecules and steric repulsions caused by the introducing of three phenyl at the meso- positions of corrole macrocycle.
