A3B-Type Phthalocyanine-Based Homoleptic Lanthanide(III) Double-Decker π-Radical Complexes Bearing Functional Hydroxy Groups: Synthetic Approach, Spectral Properties and Electrochemical Study

The sandwich lanthanide(III) complexes (BnO,Bu)Pc(2)Ln (Pc-Bno,Pc-Bu = 2 -benzyloxy-9,10,16,17,23,24-hexa-n-butylphthalocyaninate; Ln = Eu, Lu) (1a, 1b) were obtained from [Ln(acac)(3)]. nH(2)O and (PcH2)-Pc-BnO,Bu by heating these compounds in n-hexadecanol, and then treating the reaction solution with H2SO4 to yield the corresponding neutral double-decker complexes (HO,Bu)Pc(2)Ln (Pc-HO,Pc-Bu = 9,10,16,17,23,24-hexa-n-butyl-2-hydroxyphthalocyaninate) (2a, 2b), which are promising structural building blocks and stable phenolic hydroxy group containing it-radical species. A combination of UV/Vis/NIR, NMR spectroscopy, MALDI-TOF mass spectrometry, cyclic voltammetry and spectroelectrochemistry provided unambiguous characterization of the newly prepared bis(phthalocyanines), and also allowed their stability and behavior in solution to be investigated.