Preparation and characterization of covalently bound tetraphenylporphyrin-silica gel stationary phases for reversed-phase and anion-exchange chromatography.

A tetraphenylporphyrin-based stationary phase for high-performance liquid chromatography is prepared by attaching a p-carboxyphenyl derivative of the porphyrin to aminopropyl silica gel through an amide bond. This stationary-phase support is used for the reversed-phase separation of several polycyclic aromatic hydrocarbons and is shown to exhibit novel shape selectivity toward planar aromatic solutes. Subsequent metalation of the immobilized tetraphenylporphyrin with either tin(IV) or indium(III) results in a stationary phase with anion-exchange characteristics. Both the tin(IV) and indium(III) metalloporphyrin-based stationary phases exhibit useful selectivity for the separation of aromatic sulfonates and aromatic carboxylates.