New Hexanuclear Group 11 Pyrazolate Complexes: Synthesis and Photophysical Features

Abstract

The treatment of 2,2'-di(1,2-pyrazol-3-yl)-1,1'-binaphthyl with two equivalents of appropriate monovalent group 11 precursors in the presence of a base leads to a complete exchange of the pyrazole NH protons with M(+) cations. Structural characterisation of the copper(I) complex revealed a hexanuclear complex with a pelton-wheel-like arrangement of the binaphthyl unit. As indicated by their spectroscopic data, all three complexes are isostructural. The complexes show a complex fluorescence behaviour that can be partially related to the ligand system and also to the metal sites, as indicated by the position of the fluorescence peaks and their temperature dependence and lifetimes.

Confined Metallophilicity within a Coordination Prism

“…This newly designed coordination prism that exhibits an unprecedented stacking mode represents a unique case for assessing the existence and the nature of metallophilicity within a confined space. [23,26] Further, this research suggests that there should be no generalization for the nature of metallophilicity-in this case evident metallophilicity accompanied by electron transitions seems warranted, but in other cases the effects of bridging ligands and electrostatic interactions may obscure any genuine metallophilicity. Since metallophilicity is widely considered by theoretical chemists as a type of van der Waals force, it is highly recommended that further computational assessment is performed by taking advantage of the recently developed model of DFT with long-range corrections.…”

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

“…Thiel et al reacted enantiomerically pure 2,2"-di(1,2-pyrazol-3-yl)-(S)-1,1"-binaphthyl (S)-(pyrbinapH 2 ) with [Cu(CH 3 CN) 4 ]BF 4 to give the corresponding derivative [(S)-pyrbinapCu 2 ] 3 , 10, formed by six Cu(I) centers each linking two pyrazolate units [33]. This hexanuclear copper(I) complex displays in the solid state at room temperature an emission at about 410 nm which was assigned to the naphthalene chromophore.…”

Synthesis and crystal structures of silver(I) and copper(II) complexes with p-xylylene-bridged bipyrazolyl ligands

“…Changes in the substituents on the central phenyl ring to which the pyrazolyl units are attached may result in different spatial arrangements of the two pyrazolyl rings and thus different structural motifs upon binding to metals. As one part of our ongoing research on the coordination chemistry of bipyrazoles, we report herein the synthesis and crystal structures of two new p-xylylene-bridged C 4 -linked bipyrazolyl ligands (H 2 L and H 2 L 0 , Scheme 1), in which the pyrazolyl rings are attached to the 1,4-positions of phenyl ring instead of the 1,3-positions as in our previous paper, together with three Ag(I) and one Cu(II) complexes; [Ag 2 (H 2 L) 2 ](BF 4 (4). The structural effect of the 3,5-substituents on the conformations of bipyrazole is discussed in this paper.…”

“…As a type of ligand for metals, they have proven to be more versatile and flexible in construction of metallosupramolecular assemblies than pyrazole itself. Recent remarkable examples as such include a Cu 6 trigonal prismatic cage [3], a Cu 6 trigonal anti-prismatic cage [4], and a series of metallo-macrocycles based on dipalladium corners [5].…”