Reaction of alkaline earth metal salts with diphenylphosphinic acid in dimethylformamide solvent afforded four coordination polymers: [Mg3(O2PPh2)6(DMF)2]·2DMF (I), [Ca(O2PPh2)2(DMF)2] (II), [Sr(O2PPh2)2(DMF)2] (III) and [Ba(O2PPh2)2(DMF)2] (IV) (where DMF is N,N-dimethylformamide). Single-crystal X-ray diffraction revealed that all four compounds produce linear chain structures in the solid state, with the Ca, Sr and Ba forming isostructural crystals. The bulk materials were characterized by FT-IR and (1)H NMR spectroscopy and elemental analyses.

Key indicators: single-crystal X-ray study; T = 150 K; mean (C-C) = 0.004 Å; R factor = 0.037; wR factor = 0.067; data-to-parameter ratio = 17.2.The title complex, aqua[1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene]( 4 -cycloocta-1,5-diene)rhodium(I) tetrafluoridoborate, [Rh(C 8 H 12 )(C 27 H 36 N 2 )(H 2 O)]BF 4 , exihibits a squareplanar geometry around the Rh(I) atom, formed by a bidentate cycloocta-1,5-diene (cod) ligand, an N-heterocylcic carbene and an aqua ligand. The complex is cationic and a BF 4 À anion balances the charge. The structure exists as a hydrogen-bonded dimer in the solid state, formed via interactions between the aqua ligand H atoms and the BF 4 À F atoms. Related literature