Heteroleptic Rare Earth Double-Decker Complexes with Porphyrinato and 2,3-Naphthalocyaninato Ligands − Preparation, Spectroscopic Characterization, and Electrochemical Studies

Abstract

A series of RE(Nc)(TBPP) (1−12) complexes [RE = La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Y, Ho, Er, Tm; Nc = 2,3-naphthalocyaninate; TBPP = meso-tetrakis(4-tert-butylphenyl)porphyrinate] and Eu[Nc(tBu)4](TClPP) [Nc(tBu)4 = tetra(tert-butyl)-2,3-naphthalocyaninate; TClPP = meso-tetrakis(4-chlorophenyl)porphyrinate] (13) have been prepared by a one-pot procedure which involves the treatment of RE(acac)3·nH2O (acac = acetylacetonate) with the corresponding metal-free porphyrins and naphthalonitriles in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in n-octanol. These novel double-deckers have been spectroscopically characterized. A one-electron reduction and three one-electron oxidations have been revealed by electrochemical methods. The potentials of all these processes depend linearly on the ionic radii of the central metal ions, giving a relatively large potential difference (0.50−0.57 V) between the first oxidation and the first reduction processes.