Synthesis, structure and evaluation of spectral, luminescent and optoelectronic properties of Zn(II) hexafluoroacetylacetonate complexes of triphenodioxazines

The synthesis of 1 : 1 and 1 : 2 complexes of Zn(ii) hexafluoroacetylacetonate with sterically crowded triphenodioxazines (TPDO) is described, and the compounds are characterized using single-crystal X-ray crystallography, NMR, and IR spectroscopy. The electronic absorption (lambda(max) = 530-630 nm) and fluorescence emission (lambda(fl)(max) = 585-660 nm) spectra of the complexes substantially (up to 100 nm) bathochromically shifted relative to the spectra of the TPDO ligands. In highly dilute solutions, the Zn(hfac)(2)-TPDO complexes partially dissociate and exist in equilibrium with the ligand to reveal unusual excitation-dependent behavior of their fluorescent spectra.