Solvent-metal interactions in bis[1,2-dicarba-closo-dodeca-boran(12)-1-yl]mercury(II) dichloromethane solvate and bis[1,12-dicarba-closo-dodecaboran(12)-1-yl]-mercury(II) tetrahydrofuran solvate

The title compounds, bis[1,2-dicarba-closo-dodecaboran(12)1-yl]mercury(II) dichloromethane solvate, [Hg(C2B10H11)(2)] . CH2Cl2, (I), and bis[1,12-dicarba-closo-dodecaboran(12)-1-yl]mercury(II) tetrahydrofuran solvate, [Hg(C2B10H11)(2)] . C4H8O, (II), were prepared in excellent yields using a robust synthetic procedure involving the reaction of HgCl2 with the appropriate monolithiocarborane. X-Ray analysis of the products revealed strong interactions between the Hg atoms in both complexes and the respective lattice solvent. The distances between the Hg-II centers and the Cl atoms of the dichloromethane solvent molecule in the ortho-carborane derivative, (I), and the O atom of the tetrahydrofuran molecule in the para-carborane complex, (II), are shorter than the sums of the van der Waals radii for Hg and Cl (3.53 Angstrom), and Hg and O (3.13 Angstrom), respectively, indicating moderately strong interactions. There are two crystallographically independent molecules in the asymmetric unit of both compounds, which, in each case, are related by differing relative positions of the cages.