Preparation and characterization of monosubstituted porphyrins immobilized on nanosilica

Abstract

Three kinds of heteroaldehydes, N-(3-triethoxysilylpropyl)-4-formyl benzamide (TPHA/SiO 2), were prepared by the reaction of terephthalaldehydic acid with different silica supports such as hexagonal SBA-15, spherical SBA-15 and amorphous SiO 2 for comparison purposes. Anchoring of this aldehyde to different supports allows the synthesis of mono-substituted porphyrins without the production of di-, tri- and tetra-substituted porphyrin side products. The exclusion of the aforementioned side products during the synthesis of monosubstituted porphyrins greatly reduced the complexity during purification of the product. Absorption spectrophotometry was performed on silica gel immobilizing porphyrin (CPTTP), free base tetraphenylporphyrin (H2TPP) and heteroaldehydes (TPHA/SiO 2) using UV-Visible instrument and confirmed the presence of porphyrin on the structure of CPTTP. © 2014 Indian Academy of Sciences.