Catalytic Oxidation of Thiols within Cavities of Phthalocyanine Network Polymers

Abstract

Two three-dimensional (3D) network polymers ( 1 and 2 ), in which zinc(II) or cobalt(II) phthalocyanines were interconnected with twisted 9,9′-spirobifluorene linkers, were synthesized in order to investigate their performance as heterogeneous catalysts for thiol oxidations. From the spectroscopic analyses of two dimers ( 3 and 4 ) as component units of the network polymers, 3 connected with a short linker revealed electronic interaction between the two phthalocyanine units. Micrometer-sized polymer particles were formed due to the condensation of the twisted 9,9′-spirobifluorene linkers in the presence of zinc or cobalt ions. The dispersed solutions of 1 and 2 had sharp Q-bands, indicating the prevention of stacking among phthalocyanine moieties within the polymers. Powdered X-ray diffraction pattern and N 2 adsorption–desorption analyses suggested that 1 created small and rigid cavities as compared with 2 through the regular spatially arrangement of the phthalocyanine moieties in the 3D networks. The photocatalytic and catalytic activities of 1 and 2 for thiol oxidations using molecular oxygen were examined. We found that the catalytic activity of 1 was higher than that of 2 having larger cavities.