Definitive crystal structure of 1,1'-bis[1,2-dicarba-<i>clos</i>o-dodecaborane(11)]

In the title compound, C4H22B20, the two {1,2-closo-C2B10H11} cages are linked across a centre of inversion with a C—C distance of 1.5339 (11) Å. By careful analysis of the structure, it is established that the non-linking cage C atom is equally disordered over cage vertices 2 and 3

Crystal structure of 1,1'-bis[1,7-dicarba-<i>closo</i>-dodecaborane(11)]

In the title compound, C4H22B20, the two {1,7-closo-C2B10H11} cages are linked across a centre of inversion, with C—C = 1.5401 (16) Å. The position of the second non-linking cage C atom was established unambiguously by geometric and crystallographic methods and there is no evidence of C/B disorder

The exopolyhedral ligand orientation (ELO) in 3-(nitrato-κO)-3,3-bis(triphenylphosphane-κP)-3-rhoda-1,2-dicarba-closo-dodecaborane(11) dichloromethane 2.2-solvate

In the title compound, [Rh(C2H11B9)(NO3)(C18H15P)2]·2.2CH2Cl2, studied as a 2.2-solvate of what was assumed to be dichloromethane, the nitrate ligand liesciswith respect to both cage C atoms. Accordingly, the compound displays a pronounced preferred exopolyhedral ligand orientation (ELO) which is traced to both the greatertransinfluence of the cage B over the cage C atoms and the greatertransinfluence of the triphenylphosphane ligands over the nitrate ligand. The overall molecular architecture therefore agrees with that of a number of similar 3-L-3,3-L′2-3,1,2-closo-MC2B9H11species in the literature.</jats:p

Reduction-induced facile isomerisation of metallacarboranes:synthesis and crystallographic characterisation of 4-Cp-4,1,2-closo-CoC₂B₉H₁₁

One-electron reduction of 3-Cp-3,1,2-closo-CoC2B9H11 followed by heating to reflux in DME (b.p. 85 °C) induces isomerisation to 4-Cp-4,1,2-closo-CoC2B9H11.</p

Steric <i>versus</i> electronic factors in metallacarborane isomerisation: nickelacarboranes with 3,1,2-, 4,1,2- and 2,1,8-NiC₂B₉ architectures and pendant carborane groups, derived from 1,1′-bis(o-carborane)

Nickelacarborane derivatives of 1,1′-bis(o-carborane) allow comment on the factors important in the isomerisation of metallacarboranes.</p

Silver Effect in Regiodivergent Gold-Catalyzed Hydroaminations

We report a silver-induced switching of regioselectivity in gold-catalyzed reactions, and we provide mechanistic evidence to suggest a true “silver effect”: that is, one that is implicated in the catalytic process itself, via σ-gold π-silver acetylides. These results are of significance because they clearly show that the use of silver as halide abstractors in gold-catalyzed reactions may result in “silver effects” when terminal alkyne substrates are involved