Luminescent Heteroleptic Tris(dipyrrinato)indium(III) Complexes

Abstract

To provide an improvement over the low fluorescence efficiencies often shown by homoleptic tris(dipyrrinato)indium(III) complexes, luminescent heteroleptic tris(dipyrrinato)indium(III) complexes bearing two types of dipyrrinato ligands are designed here by theoretical calculation and then synthesized. They possess frontier orbitals linked to suppression of the nonemissive charge-separated states; one shows a high fluorescence quantum yield (0.41) in toluene, which exceeds that of the corresponding BF2 complex.

Heteroleptic [Bis(oxazoline)](dipyrrinato)zinc(II) Complexes: Bright and Circularly Polarized Luminescence from an Originally Achiral Dipyrrinato Ligand

“…This electronic structure leads to the suppression of non‐emissive symmetry‐breaking charge separation . The validity of our strategy has been further verified by heteroleptic tris(dipyrrinato)indium(III) and (azadipyrrinato)(dipyrrinato)zinc(II) complexes that also show brighter luminescence than the corresponding homoleptic complexes. The limitation of this strategy is clear when attempting to gain bright fluorescence from a simple, non‐π‐expanded dipyrrinato ligand (for example, the left‐hand dipyrrinato ligand of 1 in Figure a).…”

Heteroleptic bis(dipyrrinato)copper(ii) and nickel(ii) complexes

“…a combination of plain ligands 1 and -extended ligand 2, scheme 1). 4,7 These d 10 homoleptic complexes exhibit brighter fluorescence than the corresponding homoleptic complexes.…”

“…2 In addition, dipyrrins can form complexes with various metals (Zn, Cu, Ni, Pd, In, Ga, Fe, Co, and Ru) by chelating them with two pyrrole nitrogens. 3,4 In many cases, the complexation proceeds spontaneously under ambient conditions. These features mean that the motif is used in supramolecules, coordination polymers, and metal-organic frameworks.…”

Heterodinuclear Group 13 Element Complexes of N4O6‐Type Dipyrrin with an Unsymmetrical Twisted Structure

“…To the best of our knowledge, this is the first example of the 1:1 complexes of the gallium‐dipyrrin (GADIPY) and indium‐dipyrrin (INDIPY) derivatives, although the tris(dipyrrinato) complexes or the porphyrin derivatives of the late group 13 elements have been reported. The tetradentate chelation of the N 2 O 2 dipyrrin unit employed in this study successfully yielded stable neutral complexes of these Lewis acidic elements in methanol.…”