A cationic rhodium(I) N-heterocyclic carbene complex isolated as an aqua adduct.

The title complex, aqua-[1,3-bis-(2,6-diiso-propyl-phen-yl)imid-az-ol-2-yl-idene](η(4)-cyclo-octa-1,5-diene)rhodium(I) tetra-fluor-ido-borate, [Rh(C(8)H(12))(C(27)H(36)N(2))(H(2)O)]BF(4), exihibits a square-planar geometry around the Rh(I) atom, formed by a bidentate cyclo-octa-1,5-diene (cod) ligand, an N-heterocylcic carbene and an aqua ligand. The complex is cationic and a BF(4) (-) anion balances the charge. The structure exists as a hydrogen-bonded dimer in the solid state, formed via inter-actions between the aqua ligand H atoms and the BF(4) (-) F atoms.