Structure and photophysical and electrochemical properties of a copper porphyrin complex with a three-dimensional framework
Wen-Tong Chen
Abstract
Porphyrins and metalloporphyrins can generally show attractive structural motifs and interesting properties. A new copper porphyrin, namely poly[[μ-chlorido-[μ 5 -5,10,15,20-tetrakis(pyridin-4-yl)-21 H ,23 H -porphine]tricopper(I)] [aquadichloridocopper(II)]], {[Cu 3 (C 40 H 24 N 8 )Cl][CuCl 2 (H 2 O)]} n ( 1 ), was synthesized by the self-assembly of copper chloride with 5,10,15,20-tetrakis(pyridin-4-yl)-21 H ,23 H -porphine under solvothermal conditions. The structure of this copper porphyrin was characterized by single-crystal X-ray crystallography and elemental analysis. The porphyrin macrocycle shows a distorted saddle geometry, with the four pyrrole rings slightly distorted in an alternating mode either upwards or downwards. The copper ions show three-coordinated triangular and four-coordinated square-planar geometries. Every copper–porphyrin unit connects to 12 others via four μ 4 -bridging Cu 2 Cl moieties to complete the three-dimensional framework of compound 1 , with isolated CuCl 2 (H 2 O) units located in the voids. This copper porphyrin displays a red photoluminescence. Electrochemical measurements showed that compound 1 has two redox waves ( E 1/2 = −160 and 91 mV).