@article{BaierKellingJackstelletal.2013,
  author    = {Baier, Heiko and Kelling, Alexandra and Jackstell, Ralf and Holdt, Hans-J{\"u}rgen},
  title     = {Rhodium(I) and Silver(I) Complexes of 4,5-Dicyano-1,3-dimesityl- and 4,5-Dicyano-1,3-dineopentylimidazol-2-ylidene},
  series = {Zeitschrift f{\"u}r anorganische und allgemeine Chemie},
  volume    = {639},
  journal   = {Zeitschrift f{\"u}r anorganische und allgemeine Chemie},
  number    = {10},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {0044-2313},
  doi       = {10.1002/zaac.201300250},
  pages     = {1731 -- 1739},
  year      = {2013},
  abstract  = {The new N-heterocyclic carbene (NHC) precursors 4,5-dicyano-1, -dimesityl- (9) and 4, 5-dicyano-1, 3-dineopentyl-2-(pentafluorophenyl)imidazoline (14) were synthesized. 9 could be determined by X-ray crystallography. With the 2-pentafluorophenyl-substituted imidazolines 9 and 14, the [AgCl(NHC)], [RhCl(COD)(NHC)], and [RhCl(CO)(2)(NHC)] complexes [NHC = 4, 5-dicyano-1, 3-dimesitylimidazol-2-ylidene (3) and 4, 5-dicyano-1, 3-dineopentylimidazol-2-ylidene (4)] were obtained. Crystal structures of [AgCl(3)] (15), [RhCl(COD)(3)] (17), [RhCl(COD)(4)] (18), and [RhCl(CO)(2)(3)] (19) were solved and with the crystal data of 19, the percent buried volume (\%V-bur) of 31.8(+/- 0.1)\% was determined for NHC 3. Infrared spectra of the imidazolines 9 and 14 and of the complexes 15-20 were recorded and the CO stretching frequencies of complexes 19 and 20 were used to determine the 3 ( (-1)) and 4 ( (-1)), thus proving that 1, 3-substitution of maleonitrile-NHCs does not have a significant effect for the high -acceptor strength of these carbenes.},
  language  = {en}
}
@article{HalaskaPevecStrauchetal.2013,
  author    = {Halaska, Jozef and Pevec, Andrej and Strauch, Peter and Kozlevcar, Bojan and Koman, Marian and Moncol, Jan},
  title     = {Supramolecular hydrogen-bonding networks constructed from copper(II) chlorobenzoates with nicotinamide - Structure and EPR},
  series = {Polyhedron : the international journal of inorganic and organometallic chemistry},
  volume    = {61},
  journal   = {Polyhedron : the international journal of inorganic and organometallic chemistry},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0277-5387},
  doi       = {10.1016/j.poly.2013.05.032},
  pages     = {20 -- 26},
  year      = {2013},
  abstract  = {Nicotinamide (nia) has been employed as a supramolecular reagent in the synthesis of four copper(II) chloro- and dichlorobenzoate (Clbz/Cl(2)bz) complexes. The structures of the compounds [Cu(2-Clbz)(2) (nia)(2)(H2O)(2)] (1), icu(4-clbz)(2)(nia)(2)(H2O)(2)] (2), [Cu(3,5-Cl(2)bz)(2)(nia)(2)(H2O)(2)] (3), and [Cu(2,5-Cl(2)bz)(2) (nia)(2)(H2O)]center dot H2O (4) were determined. All the investigated compounds 1-4 reveal water molecules as coordinated. Their structures show distorted octahedral chromophores (CuN2O2O)-N-II'(2), though some are better described as square-planar or square-pyramid due to a large deviation of the axial ligand away from the octahedral z-axis along with different Cu center dot center dot center dot O (axial) lengths. The equatorial positions are occupied in all four cases by two nitrogen (nia-py) atoms and two carboxylate oxygen atoms of two Clbz/Cl(2)bz ligands, while the axial positions are occupied by water molecules. The EPR spectra reveal for all 1-4 compounds a spin state of S = 1/2, mostly with axial symmetry of the spectra. Their resolution is clearly dependant to the crystal symmetry related equivalence of the magnetic sites. The coordination molecules of all compounds are connected by N-H center dot center dot center dot O and O-H center dot center dot center dot O H-bonds from nicotinamide NH2 groups, carboxylate anions and/or water molecules, which create supramolecular chains or further H-bonded into 2D sheets. Steric hindering of the chlorine atoms of the Clbz/Cl(2)bz, especially seen at the coordination of the water molecules, demonstrates its role at the coordination sphere appearance. Despite this influence, the water molecules in 1-4 always assist at the similar supramolecular H-bonded network, almost at the same manner.},
  language  = {en}
}