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Acta Cryst. (2008). E64, m369-m370    [ doi:10.1107/S1600536808001153 ]

cis-Difluoridobis(1,10-phenanthroline)chromium(III) perchlorate monohydrate

T. Birk, J. Bendix and H. Weihe

Abstract top

The title complex, [CrF2(C12H8N2)2]ClO4·H2O, displays a slightly distorted octahedral coordination geometry around the central chromium(III) ion. The Cr environment is composed of a cis arrangement of two 1,10-phenanthroline [average CrIII-N = 2.0726 (10) Å] and two fluoride [average CrIII-F = 1.8533 (6) Å] ligands. The water molecule forms a hydrogen bond to fluorine in a neighbouring cation.

Comment top

Difluoro complexes of chromium(III) with various amine ligands have received a steady interest in the literature. Areas of interest have been e.g. kinetic behavior (Delavar & Staples, 1981), solvatochromism (Kaizaki & Takemoto, 1990) and photochemical/photophysical properties (Kane-Maguire et al., 1986). From a synthetic point of view simple fluoro containing complexes exhibit some advantageous properties for synthesis in non-acidic media. The strong coordination of the small and basic fluoro ligand makes it suitable as an "inorganic" protection group, easily removed and substituted by other ligands. Only a limited number of complexes belonging to this group have been structural characterized e.g. cis-[Cr(NH3)4F2]ClO4 (Brenčič et al., 1981), cis-[Cr(en)2F2]ClO4 . NaClOO4 . H2O (Brenčič et al., 1987) and cis-[Cr(bipy)2F2]ClO4 (Yamaguchi-Terasaki et al., 2007). In this report we present the crystal structure of cis-Difluoro(1,10-phenanthroline)chromium(III) perchlorate monohydrate (1).

The structure of (1) shows a octahedral coordination geometry around the central chromium(III) ion consisting of a cis arrangment of two fluorine and two nitrogen ligator atoms (Figure 1). Comparison of the Cr—N bond distances in trans position relative to the fluoro ligand [N1: 2.0934 (15) Å and N3: 2.0797 (16) Å] show a slightly elongation compared to the corresponding in cis postion [N2: 2.0607 (15) Å and N4: 2.0566 (15) Å]. This pattern of bond lengths are similar to that found in the analogous bipyridine complex cis-Difluoro(2,2'-bipyridine)chromium(III) perchlorate, cis-[Cr(bipy)2F2]ClO4.

The overall crystal packing is predominately determined by the approximately perpendicular orientation of the two planar 1,10-phenanthroline ligands [N3—Cr—N1:87.34 (6) °, N3—Cr—N2: 96.36 (6) °] and the presence of crystal water connecting each asymmetric unit with another through hydrogen bonding from water to fluorine (Figure 2).

Related literature top

For details of the general synthesis of amine-containing difluoro complexes of chromium(III), see Glerup et al. (1970). For the structure of the analogue 2,2'-bipyridine complex, see Yamaguchi-Terasaki et al. (2007).

For related literature, see: Brenčič et al. (1981, 1987); Delavar & Staples (1981); Kaizaki & Takemoto (1990); Kane-Maguire, Wallace & Speece (1986).

Experimental top

The title complex was synthesized by reflux of trans-difluorotetrakis(pyridine)chromium(III) perchlorate and 1,10-phenanthroline in 2-methoxyethanol according to the published method (Glerup et al., 1970).

Crystal suitable for X-ray diffraction were obtained by the following method: 0.208 g of the compound was dissolved in a solution of water/acetonitrile (20 ml/10 ml) and filtered though a filter paper into a small beaker. The beaker was covered with a lid of paper and left undisturbed at room temperature for crystallization (ca 3–5 days). The crystals was harvested by gently scratching with a spatula and washed with the mother liquid.

Refinement top

All H atoms were identified in a difference Fourier map and incorporated in the refinement in a riding model, with C–H = 0.95 Å and Uiso(H) = 1.2UEq.

Computing details top

Data collection: COLLECT (Nonius, 1999); cell refinement: COLLECT (Nonius, 1999); data reduction: EVALCCD (Duisenberg et al., 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure and atom labeling scheme of cis-[Cr(phen)2F2]ClO4. H2O. Displacement ellipsoids are drawn at 50% probability. H atoms with arbitrary radii.
[Figure 2] Fig. 2. The crystal packing in cis-[Cr(phen)2F2]ClO4. H2O. Displacement ellipsoids are drawn at 50% probability. H atoms except the one originated from cystal water have been omitted.
cis-Difluorido(1,10-phenanthroline)chromium(III) perchlorate monohydrate top
Crystal data top
[CrF2(C12H8N2)2]ClO4·H2OZ = 2
Mr = 567.87F000 = 578
Triclinic, P1Dx = 1.651 Mg m−3
Hall symbol: -P 1Mo Kα radiation
λ = 0.71073 Å
a = 7.6930 (10) ÅCell parameters from 26598 reflections
b = 9.4640 (8) Åθ = 2.3–25.0º
c = 16.0610 (17) ŵ = 0.68 mm−1
α = 79.750 (7)ºT = 122 (1) K
β = 83.228 (12)ºBlock, red
γ = 88.115 (8)º0.44 × 0.41 × 0.16 mm
V = 1142.6 (2) Å3
Data collection top
Nonius KappaCCD area-detector
diffractometer		4014 independent reflections
Radiation source: fine-focus sealed tube3851 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.025
T = 122.0(10) Kθmax = 25.0º
ω and φ scansθmin = 2.3º
Absorption correction: gaussian integration
(Coppens, 1970)		h = −9→9
Tmin = 0.794, Tmax = 0.913k = −11→11
28606 measured reflectionsl = −18→19
Refinement top
Refinement on F2H-atom parameters constrained
Least-squares matrix: full  w = 1/[σ2(Fo2) + (0.1P)2]
where P = (Fo2 + 2Fc2)/3
R[F2 > 2σ(F2)] = 0.031(Δ/σ)max = 0.078
wR(F2) = 0.145Δρmax = 0.79 e Å−3
S = 1.41Δρmin = −0.51 e Å−3
4014 reflectionsExtinction correction: none
329 parameters
Crystal data top
[CrF2(C12H8N2)2]ClO4·H2Oγ = 88.115 (8)º
Mr = 567.87V = 1142.6 (2) Å3
Triclinic, P1Z = 2
a = 7.6930 (10) ÅMo Kα
b = 9.4640 (8) ŵ = 0.68 mm−1
c = 16.0610 (17) ÅT = 122 (1) K
α = 79.750 (7)º0.44 × 0.41 × 0.16 mm
β = 83.228 (12)º
Data collection top
Nonius KappaCCD area-detector
diffractometer		4014 independent reflections
Absorption correction: gaussian integration
(Coppens, 1970)		3851 reflections with I > 2σ(I)
Tmin = 0.794, Tmax = 0.913Rint = 0.025
28606 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.031329 parameters
wR(F2) = 0.145H-atom parameters constrained
S = 1.41Δρmax = 0.79 e Å−3
4014 reflectionsΔρmin = −0.51 e Å−3
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*/Ueq
Cr10.86046 (3)0.55137 (3)0.266315 (15)0.01130 (17)
Cl10.42169 (6)0.04581 (5)0.27329 (3)0.02027 (19)
F11.08731 (13)0.60734 (11)0.22192 (6)0.0170 (3)
F20.92467 (13)0.41293 (11)0.35383 (6)0.0175 (3)
N10.76931 (19)0.68048 (16)0.16003 (9)0.0124 (3)
N30.6003 (2)0.52586 (16)0.31812 (9)0.0136 (3)
N40.83917 (19)0.70717 (16)0.34149 (9)0.0146 (3)
N20.8597 (2)0.40348 (16)0.18644 (10)0.0144 (3)
C120.7592 (2)0.60779 (19)0.09479 (11)0.0137 (4)
C10.7256 (2)0.81930 (19)0.14890 (12)0.0171 (4)
H10.73150.87070.19420.020*
C240.5533 (2)0.61063 (18)0.37709 (10)0.0138 (4)
C230.6826 (2)0.70727 (19)0.39112 (10)0.0139 (4)
C130.4814 (2)0.43556 (19)0.30366 (12)0.0173 (4)
H130.51340.37510.26290.021*
C150.2655 (2)0.5115 (2)0.40692 (12)0.0197 (4)
H150.15100.50560.43670.024*
C110.8100 (2)0.45883 (19)0.10871 (11)0.0140 (4)
C100.9151 (2)0.26736 (19)0.20079 (12)0.0191 (4)
H100.94930.22770.25510.023*
C180.4782 (3)0.7862 (2)0.50181 (12)0.0202 (4)
H180.45310.84340.54480.024*
C220.9635 (2)0.7957 (2)0.35158 (12)0.0183 (4)
H221.07300.79640.31730.022*
C70.8106 (2)0.3795 (2)0.04286 (12)0.0171 (4)
C190.6457 (2)0.79451 (19)0.45241 (11)0.0164 (4)
C90.9245 (3)0.1812 (2)0.13812 (13)0.0224 (4)
H90.96710.08510.14970.027*
C200.7809 (3)0.8874 (2)0.46210 (12)0.0208 (4)
H200.76280.94820.50350.025*
C80.8722 (3)0.2354 (2)0.05988 (13)0.0212 (4)
H80.87710.17710.01730.025*
C30.6631 (2)0.8201 (2)0.00597 (12)0.0204 (4)
H30.62780.8691−0.04640.024*
C210.9360 (3)0.8881 (2)0.41136 (13)0.0231 (4)
H211.02600.95120.41680.028*
C170.3534 (2)0.6962 (2)0.48787 (12)0.0201 (4)
H170.24210.69330.52070.024*
C20.6715 (3)0.8918 (2)0.07198 (12)0.0214 (4)
H20.64060.99080.06610.026*
C60.7569 (2)0.4481 (2)−0.03680 (12)0.0198 (4)
H60.75600.3946−0.08150.024*
C50.7068 (3)0.5882 (2)−0.05005 (12)0.0205 (4)
H50.67090.6311−0.10350.025*
C40.7071 (2)0.6730 (2)0.01613 (11)0.0168 (4)
C160.3878 (2)0.6065 (2)0.42455 (11)0.0164 (4)
C140.3132 (2)0.4267 (2)0.34592 (12)0.0205 (4)
H140.23120.36300.33330.025*
O30.3942 (2)−0.10036 (16)0.26532 (11)0.0357 (4)
O20.5918 (3)0.0563 (2)0.29920 (14)0.0537 (5)
O40.2950 (3)0.0879 (2)0.33573 (14)0.0617 (7)
O10.4169 (4)0.1381 (2)0.19353 (12)0.0641 (7)
O50.1662 (2)0.87161 (16)0.12962 (9)0.0286 (4)*
H5A0.25680.90690.16470.034*
H5B0.13060.77420.16640.034*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cr10.0102 (2)0.0141 (2)0.0097 (2)−0.00101 (14)0.00002 (14)−0.00270 (15)
Cl10.0265 (3)0.0206 (3)0.0139 (3)0.0005 (2)−0.0013 (2)−0.0043 (2)
F10.0123 (5)0.0210 (6)0.0168 (6)−0.0029 (4)0.0026 (4)−0.0030 (4)
F20.0128 (5)0.0227 (6)0.0152 (5)−0.0009 (4)−0.0013 (4)0.0017 (4)
N10.0098 (7)0.0129 (7)0.0140 (7)−0.0007 (6)0.0019 (6)−0.0029 (6)
N30.0110 (7)0.0157 (7)0.0139 (7)−0.0005 (6)−0.0028 (5)−0.0011 (6)
N40.0136 (8)0.0185 (8)0.0117 (7)−0.0003 (6)−0.0011 (6)−0.0024 (6)
N20.0140 (8)0.0136 (8)0.0154 (8)−0.0016 (6)0.0019 (6)−0.0038 (6)
C120.0090 (8)0.0195 (9)0.0125 (9)−0.0024 (7)0.0010 (7)−0.0038 (7)
C10.0124 (9)0.0166 (9)0.0224 (10)0.0005 (7)−0.0003 (7)−0.0051 (7)
C240.0128 (9)0.0153 (8)0.0114 (8)0.0024 (7)−0.0023 (6)0.0027 (7)
C230.0146 (9)0.0161 (8)0.0107 (8)0.0029 (7)−0.0030 (7)−0.0010 (7)
C130.0182 (9)0.0174 (9)0.0164 (9)−0.0010 (7)−0.0055 (7)−0.0008 (7)
C150.0110 (9)0.0219 (9)0.0217 (10)0.0009 (7)−0.0006 (7)0.0073 (7)
C110.0102 (8)0.0181 (9)0.0139 (9)−0.0024 (7)0.0015 (7)−0.0046 (7)
C100.0183 (9)0.0150 (9)0.0231 (10)−0.0012 (7)−0.0011 (8)−0.0010 (7)
C180.0239 (10)0.0233 (10)0.0127 (9)0.0108 (8)−0.0020 (7)−0.0030 (7)
C220.0144 (9)0.0245 (10)0.0171 (9)−0.0034 (8)−0.0022 (7)−0.0056 (7)
C70.0129 (9)0.0209 (9)0.0183 (9)−0.0049 (7)0.0032 (7)−0.0080 (7)
C190.0206 (10)0.0170 (9)0.0113 (9)0.0027 (7)−0.0047 (7)−0.0001 (7)
C90.0221 (10)0.0138 (9)0.0307 (11)−0.0008 (8)0.0029 (8)−0.0061 (8)
C200.0265 (10)0.0226 (10)0.0164 (9)0.0025 (8)−0.0071 (8)−0.0097 (7)
C80.0193 (10)0.0206 (10)0.0249 (10)−0.0043 (8)0.0057 (8)−0.0121 (8)
C30.0167 (9)0.0250 (10)0.0183 (9)0.0010 (8)−0.0031 (7)0.0000 (8)
C210.0255 (11)0.0230 (10)0.0242 (10)−0.0055 (8)−0.0084 (8)−0.0082 (8)
C170.0149 (9)0.0244 (10)0.0168 (9)0.0086 (8)0.0036 (7)0.0030 (7)
C20.0206 (10)0.0162 (9)0.0268 (10)0.0016 (8)−0.0035 (8)−0.0014 (8)
C60.0162 (9)0.0297 (10)0.0158 (9)−0.0030 (8)0.0006 (7)−0.0111 (8)
C50.0179 (10)0.0323 (11)0.0121 (9)−0.0025 (8)−0.0020 (7)−0.0054 (8)
C40.0108 (8)0.0218 (9)0.0169 (9)−0.0012 (7)0.0003 (7)−0.0017 (7)
C160.0124 (9)0.0183 (9)0.0152 (9)0.0042 (7)−0.0016 (7)0.0054 (7)
C140.0144 (9)0.0181 (9)0.0276 (10)−0.0027 (7)−0.0079 (8)0.0033 (8)
O30.0323 (9)0.0276 (8)0.0520 (10)−0.0016 (7)−0.0062 (7)−0.0190 (7)
O20.0472 (12)0.0437 (10)0.0732 (13)−0.0143 (9)−0.0298 (10)−0.0008 (10)
O40.0711 (15)0.0491 (11)0.0621 (13)−0.0118 (10)0.0385 (11)−0.0304 (10)
O10.111 (2)0.0517 (12)0.0274 (10)0.0159 (12)−0.0227 (11)0.0056 (8)
Geometric parameters (Å, °) top
Cr1—F21.8444 (10)C11—C71.401 (3)
Cr1—F11.8621 (10)C10—C91.398 (3)
Cr1—N42.0566 (15)C10—H100.9501
Cr1—N22.0607 (15)C18—C171.367 (3)
Cr1—N32.0797 (16)C18—C191.428 (3)
Cr1—N12.0934 (15)C18—H180.9501
Cl1—O41.4144 (17)C22—C211.404 (3)
Cl1—O11.4200 (18)C22—H220.9501
Cl1—O21.4310 (19)C7—C81.419 (3)
Cl1—O31.4365 (15)C7—C61.429 (3)
N1—C11.331 (2)C19—C201.423 (3)
N1—C121.363 (2)C9—C81.371 (3)
N3—C131.339 (2)C9—H90.9500
N3—C241.357 (2)C20—C211.362 (3)
N4—C221.335 (2)C20—H200.9500
N4—C231.364 (2)C8—H80.9500
N2—C101.333 (2)C3—C21.365 (3)
N2—C111.359 (2)C3—C41.406 (3)
C12—C41.401 (3)C3—H30.9500
C12—C111.436 (3)C21—H210.9500
C1—C21.404 (3)C17—C161.433 (3)
C1—H10.9501C17—H170.9500
C24—C161.403 (3)C2—H20.9500
C24—C231.436 (2)C6—C51.355 (3)
C23—C191.393 (3)C6—H60.9499
C13—C141.386 (3)C5—C41.442 (3)
C13—H130.9501C5—H50.9500
C15—C141.384 (3)C14—H140.9500
C15—C161.407 (3)O5—H5A1.0444
C15—H150.9500O5—H5B1.0283
?···??
F2—Cr1—F195.92 (5)C7—C11—C12119.83 (16)
F2—Cr1—N492.33 (5)N2—C10—C9121.87 (17)
F1—Cr1—N491.42 (5)N2—C10—H10119.1
F2—Cr1—N291.83 (6)C9—C10—H10119.0
F1—Cr1—N291.86 (5)C17—C18—C19120.56 (17)
N4—Cr1—N2174.40 (5)C17—C18—H18119.6
F2—Cr1—N389.38 (5)C19—C18—H18119.9
F1—Cr1—N3170.08 (5)N4—C22—C21121.54 (17)
N4—Cr1—N379.95 (6)N4—C22—H22119.2
N2—Cr1—N396.36 (6)C21—C22—H22119.3
F2—Cr1—N1170.54 (5)C11—C7—C8116.47 (17)
F1—Cr1—N188.67 (5)C11—C7—C6119.10 (17)
N4—Cr1—N195.83 (6)C8—C7—C6124.39 (17)
N2—Cr1—N179.72 (6)C23—C19—C20116.89 (17)
N3—Cr1—N187.34 (6)C23—C19—C18119.31 (17)
O4—Cl1—O1111.05 (15)C20—C19—C18123.80 (17)
O4—Cl1—O2108.77 (15)C8—C9—C10119.92 (17)
O1—Cl1—O2107.61 (15)C8—C9—H9120.0
O4—Cl1—O3110.09 (11)C10—C9—H9120.1
O1—Cl1—O3110.47 (12)C21—C20—C19119.31 (17)
O2—Cl1—O3108.78 (11)C21—C20—H20120.5
C1—N1—C12118.50 (15)C19—C20—H20120.1
C1—N1—Cr1128.82 (12)C9—C8—C7119.61 (18)
C12—N1—Cr1112.66 (11)C9—C8—H8120.3
C13—N3—C24118.21 (16)C7—C8—H8120.1
C13—N3—Cr1129.08 (13)C2—C3—C4119.46 (17)
C24—N3—Cr1112.64 (12)C2—C3—H3120.2
C22—N4—C23118.54 (16)C4—C3—H3120.3
C22—N4—Cr1127.53 (13)C20—C21—C22120.31 (18)
C23—N4—Cr1113.65 (12)C20—C21—H21119.8
C10—N2—C11118.64 (16)C22—C21—H21119.9
C10—N2—Cr1127.12 (13)C18—C17—C16121.10 (17)
C11—N2—Cr1113.99 (12)C18—C17—H17119.4
N1—C12—C4122.95 (16)C16—C17—H17119.6
N1—C12—C11116.89 (15)C3—C2—C1120.06 (17)
C4—C12—C11120.14 (16)C3—C2—H2120.1
N1—C1—C2121.76 (17)C1—C2—H2119.8
N1—C1—H1119.1C5—C6—C7121.37 (17)
C2—C1—H1119.2C5—C6—H6119.2
N3—C24—C16123.29 (17)C7—C6—H6119.5
N3—C24—C23117.20 (16)C6—C5—C4120.78 (17)
C16—C24—C23119.51 (17)C6—C5—H5119.7
N4—C23—C19123.39 (16)C4—C5—H5119.5
N4—C23—C24116.13 (16)C12—C4—C3117.27 (17)
C19—C23—C24120.48 (17)C12—C4—C5118.77 (17)
N3—C13—C14122.54 (18)C3—C4—C5123.94 (17)
N3—C13—H13118.9C24—C16—C15116.91 (17)
C14—C13—H13118.6C24—C16—C17119.01 (17)
C14—C15—C16119.58 (17)C15—C16—C17124.08 (17)
C14—C15—H15120.1C15—C14—C13119.45 (17)
C16—C15—H15120.3C15—C14—H14120.1
N2—C11—C7123.46 (17)C13—C14—H14120.4
N2—C11—C12116.68 (16)H5A—O5—H5B101.7
?—?—?—??
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O5—H5B···F1i1.031.692.7183 (19)175
Symmetry codes: (i) x−1, y, z.
Table 1
Selected geometric parameters (Å, °) top
Cr1—F21.8444 (10)Cr1—N22.0607 (15)
Cr1—F11.8621 (10)Cr1—N32.0797 (16)
Cr1—N42.0566 (15)Cr1—N12.0934 (15)
F2—Cr1—F195.92 (5)N4—Cr1—N379.95 (6)
F2—Cr1—N492.33 (5)N2—Cr1—N396.36 (6)
F1—Cr1—N491.42 (5)F2—Cr1—N1170.54 (5)
F2—Cr1—N291.83 (6)F1—Cr1—N188.67 (5)
F1—Cr1—N291.86 (5)N4—Cr1—N195.83 (6)
N4—Cr1—N2174.40 (5)N2—Cr1—N179.72 (6)
F2—Cr1—N389.38 (5)N3—Cr1—N187.34 (6)
F1—Cr1—N3170.08 (5)
Table 2
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O5—H5B···F1i1.031.692.7183 (19)175
Symmetry codes: (i) x−1, y, z.
Acknowledgements top

The authors are grateful to Mr Flemming Hansen (Centre of Crystallographic Studies, University of Copenhagen) for collection of the X-ray diffraction data.

references
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