Coordination Polymers with Carborane Anions:  Silver Dinitrile Complexes

Crystalline materials have been isolated and characterized from mixing the silver carborane salts Ag(CB<sub>11</sub>H<sub>12</sub>) or Ag[Co(C<sub>2</sub>B<sub>9</sub>H<sub>11</sub>)<sub>2</sub>] with nitrile ligands, either terminal acetonitrile or potentially bridging alkanedinitriles. Most of the complexes showed B−H···Ag interactions between the silver center and carborane anion. [Ag(acetonitrile)<sub>2</sub>(CB<sub>11</sub>H<sub>12</sub>)] has a hexagonal network structure. [Ag(malonitrile)<sub>2</sub>(CB<sub>11</sub>H<sub>12</sub>)] is a discrete dimeric complex, while [Ag<sub>4</sub>(succinonitrile)<sub>5</sub>(CB<sub>11</sub>H<sub>12</sub>)<sub>4</sub>], [Ag(glutaronitrile)<sub>2</sub>][Co(C<sub>2</sub>B<sub>9</sub>H<sub>12</sub>)<sub>2</sub>], and {Ag(glutaronitrile)[Co(C<sub>2</sub>B<sub>9</sub>H<sub>11</sub>)<sub>2</sub>]} all show coordination chain structures. The carborane anions in {Ag(adiponitrile)[Co(C<sub>2</sub>B<sub>9</sub>H<sub>11</sub>)<sub>2</sub>]} bridge between Ag centers to give a 3D CdSO<sub>4</sub>-related coordination polymer. The structure of [Ag(malonitrile)<sub>2</sub>](BF<sub>4</sub>) was also determined to have an unusual chiral diamondoid structure with a skewed 2-fold interpenetration.