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

A series of Pt-based heterobimetallic lantern complexes of the form [PtM­(SAc)₄(OH₂)] (M = Co, <b>1</b>; Ni, <b>2</b>; Zn, <b>3</b>) 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, <b>4</b>; Ni, <b>5</b>; Zn, <b>6</b>), or alternatively dried in vacuo to the dehydrated species [PtM­(SAc)₄] (M = Co, <b>7</b>; Ni, <b>8</b>; Zn, <b>9)</b>. The Co- and Ni-containing species exhibit PtM bonding in solution and the solid state. In the structurally characterized compounds <b>1</b>–<b>6</b>, 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 <i>J</i>-coupling values of −12.7 cm^–1 (<b>1</b>), −50.8 cm^–1 (<b>2</b>), −6.0 cm^–1 (<b>4</b>), and −12.6 cm^–1 (<b>5</b>). The Zn complexes <b>3</b> and <b>6</b> 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