Electrostatic repulsion between the cations of (1-methyl-1H-imidazole-κN³)(2,2′:6′,2′′-terpyridine-κ³N,N′,N′′)platinum(II) perchlorate nitromethane monosolvate prevents Pt...Pt interactions

Abstract

The reaction between [Pt(terpy)Cl]·2H2O (terpy = 2′,2′′:6′,2′′-terpyridine) and 1-methyl­imidazole (MIm) in the presence of two equivalents of AgClO4 in nitro­methane yields the title compound, [Pt(C15H11N3)(C4H6N2)](ClO4)2·CH3NO2. The dicationic complexes are arranged in a staggered configuration. The torsion angle subtended by the 1-methyl­imidazole ring relative to the terpyridine ring is 114.9 (5)°. Inter­molecular C—H⋯O inter­actions between the perchlorate anions and the H atoms of the terpy ligand are observed. Consideration of related phenyl­bipyridyl complexes of platinum(II), which are monocationic, leads to the conclusion that the electrostatic repulsion between the dicationic chelates prevents the formation of Pt⋯Pt inter­actions. These inter­actions are a common feature associated with the monocationic species.

Taming the Biological Activity of Pd(II) and Pt(II) Complexes with Triazolato “Protective” Groups: 1H, 77Se Nuclear Magnetic Resonance and X-ray Crystallographic Model Studies with Selenocysteine to Elucidate Differential Thioredoxin Reductase Inhibition

“…The coplanar arrangement of the triazolato and terpyridine ligands, with a torsion angle of less than 2.7°, is stabilized by weak intramolecular contacts between the terpy H6/H6″ protons and the triazolato N1 and N3 nitrogen atoms . With distances of C(H)···N from 2.947(12) to 2.965(11) Å and H···N of 2.15 to 2.19 Å as well as corresponding C–H–N angles in the range of 137.9 to 140.1°, the geometry is in agreement with values previously calculated for a planar [Pd(1-methyltetrazolato)(terpy)] 2+ complex, while in corresponding N3-coordinated imidazolato compounds, the five-membered ligand is in a near-perpendicular arrangement relative to the terpy mean plane. , The only other structurally characterized [3 + 1] complex with a similar coplanar arrangement of the two ligands is [Pt(1-phenyltetrazolato)(terpy)]BF 4 , although in octahedral osmium terpyridine tetrazolato complexes, similar close contacts have been observed …”