Syntheses and structures of Osmium(II) and Osmium(VI) <Emphasis Type="Italic">meso</Emphasis>-tetra(benzo-15-crown-5)porphyrinates according to the spectral data

The reaction of meso-tetra(benzo-15-crown-5)porphyrin (H₂TCP) with the osmium carbonyl complex Os₃(CO)₁₂ yieds the corresponding osmium(II) porphyrinate OsTCP(CO). The oxidation of OsTCP(CO) with air oxygen and hydrogen peroxide in neutral and acidic media was studied. A preparative method for the synthesis of osmium(VI) meso-tetra(benzo-15-crown-5)porphyrinate (OsO₂) TCP by the oxidation of OsTCP(CO) with 50% hydrogen peroxide in acetic acid was developed. The structures of new osmium porphyrinates were determined by IR, ¹H NMR, and UV/Vis spectroscopies.