Crystal structure of trans-diammine(1,4,8,11-tetra-aza-cyclo-tetra-decane-κ(4) N)chromium(III) tetra-chlorido-zincate chloride monohydrate from synchrotron data

Crystal structure of cis-(1,4,8,11-tetra-aza-cyclo-tetra-decane-κ4 N)bis-(thio-cyanato-κN)chromium(III) bromide from synchrotron X-ray diffraction data

The crystal structure of the title complex, cis-[Cr(NCS)2(cyclam)]Br (cyclam = 1,4,8,11-tetra-aza-cyclo-tetra-decane, C10H24N4), has been determined from synchrotron X-ray data. The asymmetric unit contains one [Cr(NCS)2(cyclam)]+ cation and one bromide anion. The CrIII ion of the complex cation is coordinated by the four N atoms of the cyclam ligand and by two N-coordinating NCS groups in a cis arrangement, displaying a distorted octa-hedral coordination sphere. The Cr-N(cyclam) bond lengths are in the range 2.075 (3) to 2.081 (3) Å while the average Cr-N(NCS) bond length is 1.996 (16) Å. The macrocyclic cyclam moiety adopts the most stable cis-V conformation. The crystal structure is stabilized by inter-molecular hydrogen bonds involving the cyclam N-H groups as donor groups, and the bromide anion and the S atom of one of the NCS ligands as acceptor groups.

Crystal structure of trans-di-chlorido-(1,4,8,11-tetra-aza-cyclo-tetra-decane-κ4 N)chromium(III) bis-(form-amide-κO)(1,4,8,11-tetra-aza-cyclo-tetra-decane-κ4 N)chromium(III) bis-[tetra-chlorido-zincate(II)]

The structure of the title compound, [CrCl2(C10H24N4)][Cr(HCONH2)2(C10H24N4)][ZnCl4]2 (C10H24N4 = 1,4,8,11-tetra-aza-cyclo-tetra-decane, cyclam; HCONH2 = formamide, fa), has been determined from synchrotron X-ray data. The asymmetric unit contains two independent halves of the [CrCl2(cyclam)]+ and [Cr(fa)(cyclam)]3+ cations, and one tetra-chlorido-zincate anion. In each complex cation, the CrIII ion is coordinated by the four N atoms of the cyclam ligand in the equatorial plane and two Cl ligands or two O-bonded formamide mol-ecules in a trans axial arrangement, displaying a distorted octa-hedral geometry with crystallographic inversion symmetry. The Cr-N(cyclam) bond lengths are in the range 2.061 (2) to 2.074 (2) Å, while the Cr-Cl and Cr-O(fa) bond distances are 2.3194 (7) and 1.9953 (19) Å, respectively. The macrocyclic cyclam moieties adopt the centrosymmetric trans-III conformation with six- and five-membered chelate rings in chair and gauche conformations. The crystal structure is stabilized by inter-molecular hydrogen bonds involving the NH or CH groups of cyclam and the NH2 group of coordinated formamide as donors, and Cl atoms of the ZnCl4 2- anion as acceptors.

Crystal structure of bis-[(oxalato-κ2O1,O2)(1,4,8,11-tetra-aza-cyclo-tetra-decane-κ4N)chromium(III)] dichromate octa-hydrate from synchrotron X-ray data

The asymmetric unit of the title compound, [Cr(C2O4)(C10H24N4)]2[Cr2O7]·8H2O (C10H24N4 = 1,4,8,11-tetra-aza-cyclo-tetra-decane, cyclam; C2O4 = oxalate, ox) contains one [Cr(ox)(cyclam)]+ cation, one half of a dichromate anion that lies about an inversion centre so that the bridging O atom is equally disordered over two positions, and four water mol-ecules. The terminal O atoms of the dichromate anion are also disordered over two positions with a refined occupancy ratio 0.586 (6):0.414 (6). The CrIII ion is coordinated by the four N atoms of the cyclam ligand and one bidentate oxalato ligand in a cis arrangement, resulting in a distorted octa-hedral geometry. The Cr-N(cyclam) bond lengths are in the range 2.069 (2)-2.086 (2) Å, while the average Cr-O(ox) bond length is 1.936 Å. The macrocyclic cyclam moiety adopts the cis-V conformation. The dichromate anion has a staggered conformation. The crystal structure is stabilized by inter-molecular hydrogen bonds involving the cyclam N-H groups and water O-H groups as donors, and the O atoms of oxalate ligand, water mol-ecules and the Cr2O72- anion as acceptors, giving rise to a three-dimensional network.

Crystal structure of bis-[cis-(1,4,8,11-tetra-aza-cyclo-tetra-deca-ne-κ4N)bis(thio-cyanato-κN)chrom-ium(III)] dichromate monohydrate from synchrotron X-ray diffraction data

The structure of the complex salt, cis-[Cr(NCS)2(cyclam)]2[Cr2O7]·H2O (cyclam = 1,4,8,11-tetra-aza-cyclo-tetra-decane, C10H24N4), has been determined from synchrotron data. The asymmetric unit comprises of one [Cr(NCS)2(cyclam)]+ cation, one half of a Cr2O72- anion (completed by inversion symmetry) and one half of a water mol-ecule (completed by twofold rotation symmetry). The CrIII ion is coordinated by the four cyclam N atoms and by two N atoms of cis-arranged thio-cyanate anions, displaying a distorted octa-hedral coordination sphere. The Cr-N(cyclam) bond lengths are in the range 2.080 (2) to 2.097 (2) Å while the average Cr-N(NCS) bond length is 1.985 (4) Å. The macrocyclic cyclam moiety adopts the cis-V conformation. The bridging O atom of the dichromate anion is disordered around an inversion centre, leading to a bending of the Cr-O-Cr bridging angle [157.7 (3)°]; the anion has a staggered conformation. The crystal structure is stabilized by inter-molecular hydrogen bonds involving the cyclam N-H groups and water O-H groups as donor groups, and the O atoms of the Cr2O72- anion and water mol-ecules as acceptor groups, giving rise to a three-dimensional network.

Crystal structure of cis-di-chlorido-(1,4,8,11-tetra-aza-cyclo-tetra-decane-κ4N)chromium(III) (oxalato-κ2O1,O2)(1,4,8,11-tetra-aza-cyclo-tetra-decane-κ4N)chromium(III) bis(perchlorate) from synchrotron data

In the asymmetric unit of the title compound, [CrCl2(C10H24N4)][Cr(C2O4)(C10H24N4)](ClO4)2 (C10H24N4 = 1,4,8,11-tetra-aza-cyclo-tetra-decane, cyclam; C2O4 = oxalate, ox), there are two independent halves of the [CrCl2(cyclam)]+ and [Cr(ox)(cyclam)]+ cations, and one perchlorate anion. In the complex cations, which are completed by application of twofold rotation symmetry, the CrIII ions are coordinated by the four N atoms of a cyclam ligand, and by two chloride ions or one oxalate bidentate ligand in a cis arrangement, displaying an overall distorted octa-hedral coordination environment. The Cr-N(cyclam) bond lengths are in the range of 2.075 (5) to 2.096 (4) Å while the Cr-Cl and Cr-O(ox) bond lengths are 2.3358 (14) and 1.956 (4) Å, respectively. Both cyclam moieties adopt the cis-V conformation. The slightly distorted tetra-hedral ClO4- anion remains outside the coordination sphere. The supra-molecular architecture includes N-H⋯O and N-H⋯Cl hydrogen bonding between cyclam NH donor groups, O atoms of the oxalate ligand or ClO4- anions and one Cl ligand as acceptors, leading to a three-dimensional network structure.

Crystal structure of tris-(trans-1,2-cyclo-hexa-ne-diamine-κ(2) N,N')chromium(III) tetra-chlorido-zincate chloride trihydrate from synchrotron data

The structure of the title double salt, [Cr(rac-chxn)3][ZnCl4]Cl·3H2O (chxn is trans-1,2-cyclo-hexa-nedi-amine; C6H14N2), has been determined from synchrotron data. The Cr(III) ion is coordinated by six N atoms of three chelating chxn ligands, displaying a slightly distorted octa-hedral coordination environment. The distorted tetra-hedral [ZnCl4](2-) anion, the isolated Cl(-) anion and three lattice water mol-ecules remain outside the coordination sphere. The Cr-N(chxn) bond lengths are in a narrow range between 2.0737 (12) and 2.0928 (12) Å; the mean N-Cr-N bite angle is 82.1 (4)°. The crystal packing is stabilized by hydrogen-bonding inter-actions between the amino groups of the chxn ligands and the water mol-ecules as donor groups, and O atoms of the water mol-ecules, chloride anions and Cl atoms of the [ZnCl4](2-) anions as acceptor groups, leading to the formation of a three-dimensional network. The [ZnCl4](2-) anion is disordered over two sets of sites with an occupancy ratio of 0.94:0.06.