Synthesis of manganese porphyrinosilica imprinted with templates using thesol-gel process

The optimized conditions for the preparation of a new manganese porphyrinos ilica-template material are reported. The manganese porphyrinosilica-templa te was prepared by the sol-gel process, by the reaction of -SO2Cl groups pr esent in the phenyl rings of MnTDC(SO2Cl)PPCl with 3-aminopropyltriethoxysi lane. The reaction produces a precursor porphyrinopropylsilyl species. whic h were then polymerized with tetraethoxysilane. The presence of manganese p orphyrin on xerogel is confirmed by ultraviolet visible absorption spectros copy and thermogravimetric analysis (TGA). The prepared materials have surf ace areas between 19 and 674 m(2) g(-1). Electron spectroscopy imaging of t he materials show that manganese distribution in the xerogel is uniform. Bo th manganese(III) porphyrinosilica-template and a similar iron(III) porphyr inosilica-template can catalyze the epoxidation of cyclooctene using iodozy lbenzene as oxygen donor. The metalloporphyrinosilica-template presents cat alytic activity similar to that of metaloporphyrin in solution. (C) 2000 El sevier Science B.V. All rights reserved.