The Nuclear Magnetic Resonance Spectra of Bisphthalocyaninatolanthanide(iii)

From the Single- to the Triple-Decker Sandwich. Effect of Stacking on the Redox and UV−Visible Spectroscopic Properties of Lutetium(III) 1,2-Naphthalocyaninate Complexes

“…The molecular form of Lu 2 (1,2-Nc) 3 , which is diamagnetic, could have been studied by NMR; unfortunately the spectrum is of no help because of the poor solubility of the compound in the common solvents and due to the number of isomers. The resonance frequency of the H 1 protons of Lu(1,2-Nc) 2 is shifted upfield compared to that of Li 2 (1,2-Nc), from 11.51 to 10.52 ppm; this has also been reported for the phthalocyanines. ,, A similar effect is observed when Lu(1,2-Nc) 2 is compared to Lu 2 (1,2-Nc) 3 , whose H 1 protons are shifted more than those of the biplanar complex; even if the 1 H NMR spectrum of the triple-decker sandwich is not well resolved, as mentioned above, no signal is visible above 9.7 ppm. This is due to the mutual influence of the ring currents.…”

Bis(2,3-naphthalocyaninato)lutetium(III) and (2,3-Naphthalocyaninato)(phthalocyaninato)lutetium(III) Complexes: Synthesis, Spectroscopic Characterization, and Electrochemistry

“…comparable with the shift observed in the phthalocyanine series,17 can be attributed to the additivity of the shielding effects of the ring-currents in the sandwich complex. 30 The Hs and Hg proton signals are only very slightly shifted downfield. The spectrum of the unsymmetrical compound Lu(2,3-Nc)-(Pc), has been obtained from solutions in DMSO-t/e and in DMF-i/7 (Figure 2).…”