Nickel(II), palladium(ii), platinum(ii), and magnesium(ii) fluorene-substituted porphyrinates: Synthesis,structure, and comparative analysis of fluorescence spectra

Using free meso-tetra(2-fluorenyl)porphine (H₂TFP) and nickel(II), palladium(II), and platinum(II) chlorides and an MgBr₂ · Et₂O complex, corresponding metal porphyrinates were synthesized with a high yield. The structures of these new compounds were studied by means of ¹H NMR spectroscopy and electron absorption spectroscopy. The fluorescence spectra of the synthesized compounds in toluene solution were comparatively analyzed. Coordination of Mg²⁺ ion with porphyrinic cycle H₂TFP significantly increases the fluorescence intensity of porphyrinic luminophore; however, the coordination of platinum metal ions (Pt²⁺, Pd²⁺) with tetrapyrrole fragment H₂TPP decreases the fluorescence intensity of porphyrinic cycle and, in the case of nickel ions, fluorescence transitions disappear