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Acta Cryst. (2008). E64, m324-m325    [ doi:10.1107/S1600536807068420 ]

Tris(propane-1,2-diamine-[kappa]2N,N')nickel(II) tetracyanidonickelate(II)

J. Kuchár and J. Cernák

Abstract top

The title compound, [Ni(C3H10N2)3][Ni(CN)4], is built up of [Ni(pn)3]2+ cations (pn is 1,2-diaminopropane) and [Ni(CN)4]2- anions. Both NiII atoms in the cation and the anion lie on a mirror plane. The respective ions interact through Coulombic forces and through a complex network of hydrogen bonds. Extended disorder associated with the cation has been resolved. The occupancies of the respective disordered positions are 0.4:0.4:0.2.

Comment top

The title compound, C13H30N10Ni2, was studied as part of a broader study of cyanocomplexes viewed as magnetic materials [Černák et al.2002). The complex is ionic and built up of [Ni(pn)3]2+cations (pn: 1,2-diaminopropane) and [Ni(CN)~4~]2– anions. Other similar ionic compounds with square tetracyanometallates(II) and [M(L—L)3]2+ cations (M = Ni, Zn, Cd; L—L: a chelating ligand), have already been described [Bubanec et al., 2004; Rodriguez et al., 1999; Paharová et al., 2007]. The Pt analogue was described by Potočňák et al. (2008).

The NiII atom in the complex cation exhibits pseudo-octahedral coordination by six nitrogen atoms from three chelate bonded pn ligands in gauche conformations. As the nickel atom occupies the position on a mirror plane the chelate bonded ligands are disordered in two positions with half occupancy (Fig. 1). Further disorder associated with the position of the methyl groups bonded to the carbon atom was detected so within the same metallocycle both R and S enantiomers are present with the same occupancy. Moreover, the structure is centrosymmetric so both opposite absolute configurations Λδδλ and Δλλδ of the chiral cations are present in the unit cell in equal quantities. It is worth noting that for the synthesis a racemic mixture of the pn ligand was used. The observed geometrical parameters are close to those observed in [Ni(pn)3][Fe(CN)5NO].H2O [Saha et al., 2005].

The charge of the cation is compensated by a [Ni(CN)4]2- anion. The latter is bisected by a mirror plane, leading to a rather regular NiC4 chromophore. The geometric characteristics are similar to those previously reported [Smékal et al., 2001].

The NiII atoms in the respective ions are not connected by covalent bonds, the shortest distance between NiII atoms being 8.527 (1) Å. The cations are connected by a complicated system of weak intermolecular hydrogen bonds of the N—H···N≡C—Ni—C≡N···H—N type, in which also the complex anions take part and where the H···N distance range is 2.103–2.488 Å.

Related literature top

For related literature, see: Paharová et al. (2007); Rodriguez et al. (1999); Saha et al. (2005); Smékal et al. (2001); Černák et al. (2002); Bubanec et al. (2004).

Experimental top

To 10 ml of a 0.1 M hot solution of NiSO4.6H2O (0.262 g, 1 mmol) 0.35 ml of pn (4 mmol) were added under continuous stirring, followed by addition of 10 ml of a 0.1 M warm solution of K2[Ni(CN)4].H2O (1 mmol). The resulting clear solution was left for crystallization at room temperature. Single crystals of the title compound, in the form of light violet needles suitable for X-ray studies, appeared after one day.

Refinement top

The structure was solved by direct method. The model (including two 50:50% disordered positions of the pn ligands, forced by the crystallographic mirror symmetry in the cation) was completed by subsequent Fourier syntheses. At this stage the calculated difference Fourier map indicated the presence of further positional disorder of the methyl groups in the pn ligands. The occupational factors refined by fixing the common isotropic thermal parameters of the concerning carbon atoms indicated 50:50 occupancy which was in the subsequent refinement cycles fixed. Finally, the hydrogen atoms were put in the calculated positions taking into account the observed disorder. Anisotropic thermal parameters were refined for all non-H atoms. All H atoms positions were calculated using the appropriate riding model with isotropic temperature factors being 1.2 times larger then temperature factors of their parent atoms. Geometrical analysis was performed using PARST (Nardelli, 1983) and SHELXL97.

Computing details top

Data collection: EXPOSE in IPDS (Stoe & Cie, 1999); cell refinement: CELL in IPDS (Stoe & Cie, 1999); data reduction: INTEGRATE in IPDS (Stoe & Cie, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: PARST (Nardelli, 1983) and SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Brandenburg, 2004); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).

Figures top
[Figure 1] Fig. 1. View of the complex cation and complex anion of the title compound. The thermal ellipsoids are drawn at 30% probability level. The disordered positions in the complex cation are shown with light colors (i: x, 0.5 - y, z).
Tris(propane-1,2-diamine-κ2N,N')nickel(II) tetracyanidonickelate(II) top
Crystal data top
[Ni(C3H10N2)3][Ni(CN)4]F000 = 936
Mr = 443.89Dx = 1.392 Mg m−3
Orthorhombic, PnmaMo Kα radiation
λ = 0.71073 Å
Hall symbol: -P 2ac 2nCell parameters from 1308 reflections
a = 9.7310 (12) Åθ = 4.6–30.5º
b = 13.3770 (14) ŵ = 1.79 mm−1
c = 16.275 (3) ÅT = 193 (2) K
V = 2118.5 (5) Å3Needle, light-violet
Z = 40.5 × 0.1 × 0.1 mm
Data collection top
Stoe IPDS
diffractometer		1947 independent reflections
Radiation source: fine-focus sealed tube1401 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.052
Detector resolution: 150 pixels mm-1θmax = 25.0º
T = 193(2) Kθmin = 2.9º
φ scansh = −11→11
Absorption correction: gaussian
(XPREP in SHELXTL; Siemens, 1996)		k = −15→15
Tmin = 0.580, Tmax = 0.815l = −19→19
14468 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.037H-atom parameters constrained
wR(F2) = 0.100  w = 1/[σ2(Fo2) + (0.0714P)2]
where P = (Fo2 + 2Fc2)/3
S = 0.92(Δ/σ)max < 0.001
1947 reflectionsΔρmax = 0.52 e Å−3
183 parametersΔρmin = −0.60 e Å−3
12 restraintsExtinction correction: none
Primary atom site location: structure-invariant direct methods
Crystal data top
[Ni(C3H10N2)3][Ni(CN)4]V = 2118.5 (5) Å3
Mr = 443.89Z = 4
Orthorhombic, PnmaMo Kα
a = 9.7310 (12) ŵ = 1.79 mm−1
b = 13.3770 (14) ÅT = 193 (2) K
c = 16.275 (3) Å0.5 × 0.1 × 0.1 mm
Data collection top
Stoe IPDS
diffractometer		1947 independent reflections
Absorption correction: gaussian
(XPREP in SHELXTL; Siemens, 1996)		1401 reflections with I > 2σ(I)
Tmin = 0.580, Tmax = 0.815Rint = 0.052
14468 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.03712 restraints
wR(F2) = 0.100H-atom parameters constrained
S = 0.92Δρmax = 0.52 e Å−3
1947 reflectionsΔρmin = −0.60 e Å−3
183 parameters
Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
Ni10.79310 (7)0.25000.07496 (4)0.0430 (2)
C10.8878 (6)0.25000.1736 (4)0.0505 (13)
N10.9497 (6)0.25000.2336 (3)0.0711 (14)
C20.7945 (5)0.1112 (3)0.0757 (3)0.0605 (10)
N20.7977 (6)0.0261 (3)0.0772 (3)0.0972 (15)
C30.6984 (5)0.2500−0.0248 (4)0.0554 (14)
N30.6348 (6)0.2500−0.0840 (4)0.0746 (15)
Ni20.26627 (6)0.25000.03265 (4)0.0396 (2)
C40.0955 (5)0.2500−0.1180 (3)0.0644 (15)
H4C0.06490.3200−0.10660.077*0.50
C50.2431 (5)0.2500−0.1451 (4)0.0757 (18)
H5C0.27990.1810−0.14610.091*0.50
H5D0.25170.2790−0.20080.091*0.50
C60.3879 (5)0.0651 (3)0.0946 (3)0.099 (2)
H6C0.44980.09860.13430.119*0.50
H6D0.4220−0.00390.08620.119*0.50
H6E0.44970.02880.13270.119*0.50
H6F0.39220.03280.04000.119*0.50
C70.2450 (5)0.0615 (3)0.1294 (3)0.0876 (16)
H7C0.18130.03020.08860.105*0.50
H7D0.26190.12150.16460.105*0.50
C80.0056 (10)0.2045 (7)−0.1810 (6)0.083 (3)0.50
H8C0.03910.1373−0.19420.124*0.50
H8D0.00670.2458−0.23070.124*0.50
H8E−0.08850.2001−0.15990.124*0.50
N40.1011 (6)0.1921 (4)−0.0397 (3)0.0509 (14)0.50
H4A0.11550.1254−0.05060.061*0.50
H4B0.01950.1984−0.01170.061*0.50
N50.3194 (6)0.3121 (4)−0.0839 (3)0.0475 (14)0.50
H5A0.29270.3780−0.08710.057*0.50
H5B0.41260.3082−0.09270.057*0.50
N60.3911 (6)0.1202 (4)0.0147 (3)0.0515 (15)0.50
H6A0.35620.0811−0.02680.062*0.50
H6B0.47960.13810.00150.062*0.50
N70.2107 (6)0.1694 (3)0.1391 (4)0.0539 (15)0.50
H7A0.25680.19490.18380.065*0.50
H7B0.11800.17630.14840.065*0.50
C90.258 (3)−0.0030 (11)0.2011 (7)0.073 (6)0.42 (3)
H9C0.32600.02520.23900.109*0.42 (3)
H9D0.2877−0.06980.18370.109*0.42 (3)
H9E0.1689−0.00800.22900.109*0.42 (3)
N80.4263 (6)0.3269 (3)0.0947 (4)0.0507 (14)0.50
H8A0.43470.30380.14780.061*0.50
H8B0.50870.31750.06810.061*0.50
N90.1551 (6)0.3770 (4)0.0749 (4)0.0532 (15)0.50
H9A0.12650.41460.03080.064*0.50
H9B0.07850.35650.10350.064*0.50
C100.181 (3)0.5209 (10)0.174 (2)0.086 (7)0.38 (3)
H10A0.22650.52880.22740.130*0.38 (3)
H10B0.08360.50670.18220.130*0.38 (3)
H10C0.19150.58270.14220.130*0.38 (3)
C110.445 (3)0.023 (2)0.1699 (11)0.138 (15)0.20
H11A0.54450.01470.16360.207*0.20
H11B0.4024−0.04150.18110.207*0.20
H11C0.42680.06900.21580.207*0.20
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Ni10.0430 (4)0.0313 (3)0.0547 (4)0.0000.0079 (3)0.000
C10.054 (3)0.038 (2)0.060 (4)0.0000.017 (3)0.000
N10.074 (4)0.085 (4)0.054 (3)0.0000.005 (3)0.000
C20.073 (3)0.041 (2)0.068 (3)−0.0044 (18)0.004 (2)−0.0087 (18)
N20.152 (5)0.0341 (18)0.106 (4)−0.005 (2)−0.001 (3)−0.0084 (19)
C30.040 (3)0.061 (3)0.065 (4)0.0000.012 (3)0.000
N30.053 (3)0.101 (4)0.070 (4)0.0000.000 (3)0.000
Ni20.0426 (4)0.0279 (3)0.0484 (4)0.0000.0071 (3)0.000
C40.057 (3)0.067 (4)0.069 (4)0.000−0.006 (3)0.000
C50.065 (4)0.110 (5)0.052 (3)0.000−0.002 (3)0.000
C60.080 (4)0.053 (3)0.164 (6)0.005 (2)−0.028 (4)0.043 (3)
C70.103 (4)0.066 (3)0.094 (4)−0.021 (3)−0.016 (3)0.041 (3)
C80.067 (6)0.099 (7)0.082 (6)−0.007 (5)−0.011 (6)−0.005 (5)
N40.052 (4)0.041 (3)0.060 (4)0.000 (3)0.009 (3)0.009 (3)
N50.050 (3)0.034 (3)0.058 (4)0.002 (2)0.008 (3)0.004 (3)
N60.052 (4)0.032 (3)0.071 (4)0.001 (2)0.008 (3)−0.003 (3)
N70.049 (3)0.053 (3)0.059 (4)0.005 (3)0.005 (3)0.007 (3)
C90.108 (16)0.044 (6)0.066 (7)−0.002 (7)0.019 (7)0.018 (5)
N80.054 (3)0.046 (3)0.052 (4)−0.002 (3)0.014 (3)−0.004 (3)
N90.055 (4)0.036 (3)0.068 (4)0.001 (3)0.017 (3)0.000 (3)
C100.083 (12)0.061 (8)0.115 (15)0.020 (8)0.008 (13)−0.006 (8)
C110.11 (2)0.20 (4)0.10 (3)−0.07 (3)0.032 (19)−0.08 (3)
Geometric parameters (Å, °) top
Ni1—C11.852 (7)C7—C10i1.457 (7)
Ni1—C2i1.856 (4)C7—C91.457 (7)
Ni1—C21.856 (4)C7—N71.490 (3)
Ni1—C31.866 (7)C7—N9i1.493 (3)
C1—N11.147 (7)C7—H7C1.0000
C2—N21.139 (5)C7—H7D1.0000
C3—N31.145 (8)C8—H8C0.9800
Ni2—N7i2.112 (6)C8—H8D0.9800
Ni2—N72.112 (6)C8—H8E0.9800
Ni2—N82.122 (6)N4—H4A0.9200
Ni2—N8i2.122 (6)N4—H4B0.9200
Ni2—N9i2.128 (6)N5—H5A0.9200
Ni2—N92.128 (6)N5—H5B0.9200
Ni2—N5i2.135 (6)N6—H6A0.9200
Ni2—N52.135 (6)N6—H6B0.9200
Ni2—N42.137 (6)N7—H7A0.9200
Ni2—N4i2.137 (6)N7—H7B0.9200
Ni2—N6i2.139 (5)C9—H9C0.9800
Ni2—N62.139 (5)C9—H9D0.9800
C4—C81.480 (10)C9—H9E0.9800
C4—N41.492 (3)N8—C6i1.492 (3)
C4—C51.503 (6)N8—H8A0.9200
C4—H4C1.0000N8—H8B0.9200
C5—N51.494 (3)N9—C7i1.493 (3)
C5—H5C0.9900N9—H9A0.9200
C5—H5D0.9900N9—H9B0.9200
C6—C111.457 (7)C10—C7i1.457 (7)
C6—N61.495 (3)C10—H10A0.9800
C6—C71.503 (6)C10—H10B0.9800
C6—H6C0.9900C10—H10C0.9800
C6—H6D0.9900C11—H11A0.9800
C6—H6E0.9900C11—H11B0.9800
C6—H6F0.9900C11—H11C0.9800
C1—Ni1—C2i89.46 (14)C9—C7—C6103.9 (11)
C1—Ni1—C289.46 (14)N7—C7—C6102.5 (4)
C2i—Ni1—C2178.9 (3)N9i—C7—C6107.5 (4)
C1—Ni1—C3179.7 (2)C9—C7—H7C109.7
C2i—Ni1—C390.54 (14)N7—C7—H7C109.7
C2—Ni1—C390.54 (14)C6—C7—H7C109.7
N1—C1—Ni1178.2 (5)C10i—C7—H7D113.2
N2—C2—Ni1178.6 (5)C4—C8—H8C109.5
N3—C3—Ni1176.9 (5)C4—C8—H8D109.5
N7—Ni2—N892.6 (2)H8C—C8—H8D109.5
N7i—Ni2—N8i92.6 (2)C4—C8—H8E109.5
N7i—Ni2—N9i90.7 (2)H8C—C8—H8E109.5
N8i—Ni2—N9i80.36 (19)H8D—C8—H8E109.5
N7—Ni2—N990.7 (2)C4—N4—Ni2108.0 (3)
N8—Ni2—N980.36 (19)C4—N4—H4A110.1
N8i—Ni2—N5i93.3 (2)Ni2—N4—H4A110.1
N9i—Ni2—N5i95.7 (2)C4—N4—H4B110.1
N8—Ni2—N593.3 (2)Ni2—N4—H4B110.1
N9—Ni2—N595.7 (2)H4A—N4—H4B108.4
N7—Ni2—N494.3 (2)C5—N5—Ni2104.8 (3)
N8—Ni2—N4171.73 (19)C5—N5—H5A110.8
N9—Ni2—N494.9 (2)Ni2—N5—H5A110.8
N5—Ni2—N480.42 (19)C5—N5—H5B110.8
N7i—Ni2—N4i94.3 (2)Ni2—N5—H5B110.8
N8i—Ni2—N4i171.73 (19)H5A—N5—H5B108.9
N9i—Ni2—N4i94.9 (2)C6—N6—Ni2105.7 (3)
N5i—Ni2—N4i80.42 (19)C6—N6—H6A110.6
N7i—Ni2—N6i80.95 (19)Ni2—N6—H6A110.6
N8i—Ni2—N6i92.4 (2)C6—N6—H6B110.6
N9i—Ni2—N6i168.7 (2)Ni2—N6—H6B110.6
N5i—Ni2—N6i93.3 (2)H6F—N6—H6B108.4
N4i—Ni2—N6i93.3 (2)H6A—N6—H6B108.7
N7—Ni2—N680.95 (19)C7—N7—Ni2110.5 (4)
N8—Ni2—N692.4 (2)C7—N7—H7A109.5
N9—Ni2—N6168.7 (2)Ni2—N7—H7A109.5
N5—Ni2—N693.3 (2)C7—N7—H7B109.5
N4—Ni2—N693.3 (2)Ni2—N7—H7B109.5
C8—C4—N4113.6 (5)H7A—N7—H7B108.1
C8—C4—C5111.2 (5)C7—C9—H9C109.5
N4—C4—C5102.5 (4)C7—C9—H9D109.5
C8—C4—H4C109.8C7—C9—H9E109.5
N4—C4—H4C109.8C6i—N8—Ni2106.6 (4)
C5—C4—H4C109.8C6i—N8—H8A110.4
N5—C5—C4106.2 (4)Ni2—N8—H8A110.4
N5—C5—H5C110.5C6i—N8—H8B110.4
C4—C5—H5C110.5Ni2—N8—H8B110.4
N5—C5—H5D110.5H8A—N8—H8B108.6
C4—C5—H5D110.5C7i—N9—Ni2109.5 (3)
H5C—C5—H5D108.7C7i—N9—H9A109.8
C11—C6—N6155.9 (13)Ni2—N9—H9A109.8
C11—C6—C791.4 (13)C7i—N9—H9B109.8
N6—C6—C7111.3 (4)Ni2—N9—H9B109.8
N6—C6—H6C109.4H9A—N9—H9B108.2
C7—C6—H6C109.4C7i—C10—H10A109.5
N6—C6—H6D109.4C7i—C10—H10B109.5
C7—C6—H6D109.4H10A—C10—H10B109.5
H6C—C6—H6D108.0C7i—C10—H10C109.5
C7—C6—H6E108.1H10A—C10—H10C109.5
C7—C6—H6F111.3H10B—C10—H10C109.5
H6E—C6—H6F108.8C6—C11—H11A109.5
C9—C7—N7120.5 (7)C6—C11—H11B109.5
C10i—C7—N9i117.6 (14)H6E—C11—H11B108.6
C10i—C7—C6127.2 (9)C6—C11—H11C109.5
Symmetry codes: (i) x, −y+1/2, z.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N4—H4A···N2ii0.922.243.140 (7)167
N5—H5A···N2iii0.922.173.083 (6)169
N5—H5B···N30.922.303.180 (8)159
N6—H6A···N2ii0.922.233.073 (7)152
N6—H6B···N30.922.543.349 (7)147
N7—H7A···N1iv0.922.423.295 (8)158
N7—H7B···N1v0.922.363.159 (7)145
N8—H8A···N1iv0.922.072.985 (8)179
N9—H9A···N2iii0.922.423.212 (8)144
Symmetry codes: (ii) −x+1, −y, −z; (iii) −x+1, y+1/2, −z; (iv) x−1/2, y, −z+1/2; (v) x−1, y, z.
Table 1
Selected geometric parameters (Å) top
Ni1—C11.852 (7)Ni2—N92.128 (6)
Ni1—C21.856 (4)Ni2—N52.135 (6)
Ni1—C31.866 (7)Ni2—N42.137 (6)
Ni2—N72.112 (6)Ni2—N62.139 (5)
Ni2—N82.122 (6)
Table 2
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N4—H4A···N2i0.922.243.140 (7)167
N5—H5A···N2ii0.922.173.083 (6)169
N5—H5B···N30.922.303.180 (8)159
N6—H6A···N2i0.922.233.073 (7)152
N6—H6B···N30.922.543.349 (7)147
N7—H7A···N1iii0.922.423.295 (8)158
N7—H7B···N1iv0.922.363.159 (7)145
N8—H8A···N1iii0.922.072.985 (8)179
N9—H9A···N2ii0.922.423.212 (8)144
Symmetry codes: (i) −x+1, −y, −z; (ii) −x+1, y+1/2, −z; (iii) x−1/2, y, −z+1/2; (iv) x−1, y, z.
Acknowledgements top

This work was supported by the Slovak Grant Agency VEGA (grant No. 1/3550/06) and by APVV grant No. 20–005204. The authors thank Professor Werner Massa (Phillips Universität, Marburg) for kind permission to use the diffractometer.

references
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