Substituent Influence on Structural and Luminescent Diversities of Cu₃(pyrazolate)₃-Cu_nI_n Coordination Supramolecular Isomers

Abstract

Three photoluminescent isomeric complexes [Cu3(L4)3]2[CuI]2 (labeled as complexes 1, 2, and 3) were prepared from the same bifunctional organic ligand H L4 (3-(4-pyridyl)-5-methyl-1H-pyrazole) and CuI by careful manipulation of the reaction conditions. Planar trinuclear Cu3(L4)3 and CuI/Cu2I2 units are integrated via N–Cu coordination bonds into Cu3Pz3-Cu n I n systems (Pz = pyrazolate). Complex 1 is a discrete supramolecular aggregate via cooperative π-acid···base (Cu3···I) and Cu···Cu interactions. Complexes 2 and 3 are 2-fold interpenetrated three-dimensional frameworks. The small size of the Cu n I n (n = 1 or 2) units and structural diversities in such Cu3Pz3-Cu n I n systems were realized by preinstalling a methyl group on pyrazole at the 5-position of the ligand. The three complexes exhibit subtly different yellow emissions under UV irradiation in their solid states, originating from their respective triplet excited states of the supramolecular coordination luminophores. These results demonstrate that the structural and luminescent diversities of the Cu3Pz3-Cu n I n -based complexes can be regulated by substituents.

A Sublimable Dinuclear Cuprous Complex Showing Selective Luminescence Vapochromism in the Crystalline State

“…The subsequent reversion to their original emissions is usually achieved upon thermal treatment or placing in air. Emissive Cu­(I) complexes have received rapidly increasing attractiveness because of their intriguing luminescence properties including thermally activated delayed fluorescence (TADF) and promising potential for use in various fields, such as detection and sensing, biological labeling, and display visualization devices . However, vapoluminescent Cu­(I) complexes are relatively limited .…”

Trigonal Prismatic Cu6L3 Coordination Cage: Encapsulation of Aromatic Molecules and Tuned Photoluminescence

“…[8] However, the coordination cage with prismatic structure is unusual. [9] The cyclic trinuclear complexes (CTCs) based on d 10 coinage-metal (Cu(I), Ag(I), Au(I)) attracts researchers to investigate their distinguished properties, especially their photoluminescence properties, [10] as well as metallophilicity, [11] p-acid/base chemistry, [12] and host-guest chemistry. [13] For example, Omary et.…”

Tuning the architectures and luminescence properties of Cu(i) compounds of phenyl and carboranyl pyrazoles: the impact of 2D versus 3D aromatic moieties in the ligand backbone

“…32 Furthermore, pyrazole ligands employed in such polynuclear Cu(I) compounds are deprotonated (pyrazolate ligands) or neutral pyrazolyl-pyridine/pyrimidine combinations. 32,[40][41][42][43][44] To our knowledge, there is only one report on a neutral monodentate onlypyrazole (not having other nitrogenated substituents) based Cu(I) complex. 45 There are however some more reports on neutral polypyrazolyl ligands, leading to a wide variety of coordination polymers.…”