Heterobimetallic Lantern Complexes That Couple Antiferromagnetically through Noncovalent Pt···Pt Interactions

Abstract

A series of Pt-based heterobimetallic lantern complexes of the form [PtM(SAc)4(OH2)] (M = Co, 1; Ni, 2; Zn, 3) were prepared using a facile, single-step procedure. These hydrated species were reacted with 3-nitropyridine (3-NO2py) to prepare three additional lantern complexes, [PtM(SAc)4(3-NO2py)] (M = Co, 4; Ni, 5; Zn, 6), or alternatively dried in vacuo to the dehydrated species [PtM(SAc)4] (M = Co, 7; Ni, 8; Zn, 9). The Co- and Ni-containing species exhibit Pt-M bonding in solution and the solid state. In the structurally characterized compounds 1-6, the lantern units form dimers in the solid state via a short Pt···Pt metallophilic interaction. Antiferromagnetic coupling between 3d metal ions in the solid state through noncovalent metallophilic interactions was observed for all the paramagnetic lantern complexes prepared, with J-coupling values of -12.7 cm(-1) (1), -50.8 cm(-1) (2), -6.0 cm(-1) (4), and -12.6 cm(-1) (5). The Zn complexes 3 and 6 also form solid-state dimers, indicating that the formation of short Pt···Pt interactions in these complexes is not predicated on the presence of a paramagnetic 3d metal ion. These contacts and the resultant antiferromagnetic coupling are also not unique to heterobimetallic lantern complexes with axially coordinated H2O or the previously reported thiobenzoate supporting ligand.

Imposing high-symmetry and tuneable geometry on lanthanide centres with chelating Pt and Pd metalloligands

“…The shortest intermolecular Pt···Pt distance of 5.3240(4) Å rules out any metallophillic Pt···Pt interactions similar to those observed for the related heterobimetallic lantern complexes. 40 , 41 Likely, the charge on the complexes and the packing with the counter ions both contribute to suppress Pt···Pt interactions. However, the fact that metallophillic interactions have been observed in some of the anionic lantern complexes of the divalent 3d metals, 43 points to packing effects involving the counter ions as the main reason.…”

Paramagnetic One-Dimensional Chain Complex Consisting of Three Kinds of Metallic Species Showing Magnetic Interaction through Metal–Metal Bonds

“…The study of heterometallic complexes continually leads researchers toward new compound creation by the combination of metallic species to afford diverse structural, electronic, magnetic properties, and catalytic activity. − Among these new compounds, heteronuclear metal string complexes (HMSCs), where two or three metals are regularly aligned as several strings with metal–metal bonds, have been the focus of attention due to their potential applications, which are not found in extended metal atom chains comprised of homometals. , For example, an asymmetric pentanuclear complex aligned as Ni–Ru–Ru–Ni–Ni shows a negative differential resistance expecting a molecular rectifier, and a heterotrimetallic complex aligned as Mo–Mo–Ni shows an extraordinarily large ferromagnetic coupling thorough metal–metal bonds, which are attributed to abnormal electronic structures induced by connecting multiple metals. Several HMSCs, − as well as pioneered heterometallic complexes, − have been reported. Rational and systematic synthesis methods are currently being explored and sequential synthesis methods for trinuclear complexes are suggested …”

Thiolate-Thione Redox-Active Ligand with a Six-Membered Chelate Ring via Template Condensation and Its Pt(II) Complexes

“…Herein, we report a serendipitous discovery of a new, redox-active six-membered chelate ring with two S-donor atoms. In recent years, numerous heterobimetallic lantern (paddlewheel) complexes with thiocarboxylate ligands were prepared. − These compounds are of interest as building blocks for quasi-1D structures including dimers and extended chains with unusual magnetic − properties. Thiocarboxylate ligands have ensured clean preparation in good yields of these complexes because the soft S donor binds well to soft metals such as Pt and Pd, , while the harder O donor binds to a variety of 3 d and s block metals.…”