Polynuclear pyrazolate complexes of copper. Crystal and molecular structures of [Cu(tmpz)]₃, [Cu(3-CO₂dmpz)(tmpzH)]₂Cu, and [Cu(4-Br-3-CO₂mepz)(4-Br-dmpzH)₂]₂ (where mepz = methylpyrazolate, dmpz = dimethylpyrazolate, and tmpz = trimethylpyrazolate) and magnetic susceptibility studies on the dinuclear complex

Abstract

. Can. J. Chem. 70, 2161 (1992).The reaction of molten trimethylpyrazole (tmpzH) with copper metal shot in air yields a mixture of the trinuclear cop-per (1) [Traduit par la rtdaction]

Ligand-Unsupported Metal−Metal (M = Cu, Ag) Interactions between Closed-Shell d10 Trinuclear Systems

“…Very similar molecular pairs were recognized in the crystal lattices of the pyrazolato-bridged trimers [Cu(3,5-Me 2 pz)] 3 (Cu−Cu = 2.946 Å),17a [Cu(3,4,5-Me 3 pz)] 3 (Cu−Cu = 3.069 Å),17b and [Ag(pz)] 3 (Ag−Ag = 3.431 Å), but their significance was not elaborated. Unsupported Ag−Ag contacts, albeit somewhat obscured by the Coulombic interaction, have been suggested in the ionic [M(en) n ][Ag 2 (CN) 4 ] (M = Ni, n = 3; M = Zn, n = 2) and [Ag(ImH) 2 ][ClO 4 ] complexes.…”

“…In contrast, ligand repulsion may actually be at work in preventing the triangles from becoming fully eclipsed to give three M−M contacts. That ligand effects are not responsible for the pairing is amply demonstrated by the crystal structure of [3,5-Me 2 pzH] 3 which, although it retains the planar trimeric association via hydrogen-bonding, does not display a “packing” arrangement consisting of a dimer of trimers as in [Cu(3,5-Me 2 pz)] 3 17a…”

Coinage-Metal-Based Cyclic Trinuclear Complexes with Metal–Metal Interactions: Theories to Experiments and Structures to Functions

“…The crystals were then manually separated, under a microscope, from a reddish-brown powder, which was suspected to consist of Cu n Pz n polymers. A similar method was adopted to synthesize Cu 3 (Me 3 Pz) 3 two years later . The reaction of copper shot with molten HMe 3 Pz in the presence of a limited amount of oxygen at 142 °C for 40 h afforded Cu 3 (Me 3 Pz) 3 and other unidentified Cu compounds.…”

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.…”

“…Planar dimeric and trimeric copper(I) complexes with small ligands have a strong propensity to aggregate in the solid states. Examples include the pyrazolyl‐supported “dimers of trimers” of the type [Cu 3 (3,4,5‐R 2 R′pyrazolyl) 3 ] 2 [R=Me, R′=H ( 112 ); R=R′=Me ( 113 ); R=Me, R′=C 5 H 4 N ( 114 )]) and [Cu 3 {2‐[3(5)‐pyrazolyl]pyridine} 3 ] 2 ( 115 ) as shown in Figure . 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 a EtOH/NH 3 ⋅ H 2 O solution of HPpz and CuBr, and 115 was prepared from the reaction of the deprotonated ligand and [Cu(CH 3 CN) 4 ][PF 6 ].…”