Novel Thermochromism Relating to Supramolecular Cuprophilic Interaction: Design, Synthesis, and Luminescence of Copper(I) Pyrazolate Trimer and Polymer

Abstract

Solvothermal reactions of 4-(pyrid-4'-yl)-3,5-dimethylpyrazole (HPpz) with CuBr in two mixed solvents, NH3.H2O/EtOH and NH3.H2O/MeCN, afforded respectively a copper(I) trimer, [Cu(Ppz)]3(1), and a polymer, {[Cu(Ppz)]3[CuCN] 3} (2), both containing the [Cu(Ppz)]3 entity as a building block. The products were found to be photoluminescent and, more interestingly, when cooled from room temperature to 10 K, they showed a blue shift followed by a red shift (hereafter shortened to a red-after-blue shift) of emission.

Synthetic Diversity and Luminescence Properties of ArN(PPh2)2‐Based Copper(I) Complexes

“…Complexes 3 – 6 exhibit chromism when the ground solids are cooled (they return to their original emissions at r.t.) as shown in Figure (c). The blueshift upon cooling at 77 K for complexes 3 – 6 can be attributed either to the structural changes of the multiplex excimer or lattice contraction . Emission spectra of complexes 3 – 6 at 77 K show peaks at around the 490–520 nm region.…”

Cuprophilic Interactions in and between Molecular Entities

“…Twenty-twom ultinuclear Cu I species (109-130)p ossibly with unsupported cuprophilic interactions have been structurally determined by X-ray crystallography.A si llustrated in [167] ;R= R' = Me (113) [168] ;R= Me, R' = C 5 H 4 N( 114)]) [169] and [Cu 3 {2-[3(5)-pyrazolyl]pyridine} 3 ] 2 (115) [170] as shown in Figure 5. Compounds 112-115 were prepared by four different methods: 112 and 113 were obtained from the reaction of the free ligand with Cu(OH) 2 and Cu metal, respectively, 114 was obtained by heating of aE tOH/NH 3 ·H 2 Os olution of HPpz and CuBr,a nd 115 was prepared from the reaction of the depro- Chem.…”

Cu(I) hybrid inorganic–organic materials with intriguing stimuli responsive and optoelectronic properties

“…A peculiar thermoluminescent behaviour was observed for 6 which shows a third bound state and three emission bands with relative intensities changing with temperature. In particular, a green emission (510 nm) dominates at low temperature, a lime green emission (560 Structural changes of the multiplex excimer were invoked also to elucidate the two-directional chromism observed for the first time by Yin et al [31] in trimeric [Cu(Ppz)] 3 , 7, and polymeric {[Cu(Ppz)] 3 [CuCN] 3 }, 8, obtained by reaction of CuBr with 4-(pyrid-4′-yl)-3,5-dimethylpyrazole (HPpz) and containing the [Cu(Ppz)] 3 entity as a building block.…”