Synthesis and catalytic behavior of tetrakis(4-carboxyphenyl) porphyrin-periodic mesoporous organosilica

Abstract

The periodic mesoporous organosilica having the tetrakis(4-carboxyphenyl)porphyrin (TCPP) unit was successfully synthesized by the direct co-condensation method using microwave with the corresponding tetra-silane. The tetra-silane precursor, TCPP-silsesquioxane was prepared through the reaction of TCPP with the APTES(3-Aminopropyltrietoxysilane). And TCPP-PMOs were synthesized with sodium metasilicate as a silica source and P123 (EO20PO70EO20) as a supramolecular template at 100 °C. The TCPP-PMO-n (n = 2.5 and 5.0, n refers to the molar percentage of TCPP precursor per silica) materials had >400 m² g⁻¹ of specific surface areas with ∼8.7 nm of pore diameter. TCPP-PMOs were illustrated to give superiority in the organocatalytic hydrogen transfer reactions of various ketones such as acetophenone, cyclohexanone and pinacolone as well as good activity in the photocatalytic degradation of methylene blue (MB) without metal incorporation. Fe-TCPP-PMO prepared by ion-exchange method gave also good activity and selectivity in the oxidation of cyclohexene.