Reinvestigation of bis­(2,2′-bipyridine)(nitrato-κ²O,O′)cobalt(III) hydroxide nitrate tetra­hydrate

Single crystals of the title compound, [Co(NO₃)(C₁₀H₈N₂)₂](OH)(NO₃)·4H₂O, were obtained from a Co²⁺–2,2′-bipyridine–CrO₄²⁻ mixture as the second crystalline product. The present single-crystal study confirms a previous refinement [Reimann, Zocchi, Mighell & Santoro (1971). Acta Cryst. B27, 2211–2218], and also includes all H-atom positions, which were identified from a difference map. The structure displays an O—H...O hydrogen-bonding network between the non-coordinated nitrate group, the hydroxide anion and the water mol­ecules, forming a framework around the distorted octahedral Co complex. A twofold rotation axis passes through Co and the nitrato ligand.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.043
• wR factor = 0.123
• Data-to-parameter ratio = 14.5

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT230_ALERT_2_B Hirshfeld Test Diff for    O12    -   N11     ..      13.24 su
PLAT417_ALERT_2_B Short Inter D-H..H-D       H12    ..  H21     ..       1.69 Ang.

Alert level C
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT230_ALERT_2_C Hirshfeld Test Diff for    O11    -   N11     ..       6.03 su
PLAT244_ALERT_4_C Low   'Solvent' Ueq as Compared to Neighbors for        N21
PLAT355_ALERT_3_C Long    O-H Bond (0.82A)   O3     -   H31    ...       1.02 Ang.
PLAT764_ALERT_4_C Overcomplete CIF Bond List Detected (Rep/Expd) .       1.13 Ratio

Alert level G
PLAT794_ALERT_5_G Check Predicted Bond Valency for Co1         (3)       3.68

   0 ALERT level A = In general: serious problem
   2 ALERT level B = Potentially serious problem
   5 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

Bis(2,2'-bipyridine)(nitrato-O,O')cobalt(III) hydroxide nitrate tetrahydrate (I) was unintentionally obtained from a [Co²⁺–2,2'-bipyridine–CrO₄^2-] mixture as the second product. The first product was identified as [Co(bpy)₃](CrO₄)_0.5.NO₃.7H₂O (Wojciechowska et al., 2003). The present single-crystal study confirms the previous refinement (Reimann et al., 1971), but with all hydrogen atoms, which were visible in the difference maps, included in the refinement (Fig. 1). Two organic ligands and one nitrate ion form a distorted octahedral coordination sphere around the Co(III) ion. The differences between the Co—O_nitrate bond lengths, and the Co—O—N and Co—N—O_terminal angles are 0 Å, 0° and 180° respectively, which correlate exactly with the bidentate mode of the nitrate group (Kleywegt et al., 1985; Dowling et al., 1996). The nitrate groups, hydroxide ions and water molecules form a rich hydrogen bonding network, which surrounds the [Co(bpy)₂(NO₃-O,O')]⁺ cation and links to it via an O_water—H···O_nitrate hydrogen bond (Fig. 2).

Related literature

For an earlier structure refinement of the title compound, see: Reimann et al. (1971). For the crystal structure of [Co(bpy)₃](CrO₄)_0.5NO₃.7H₂O, see: Wojciechowska et al. (2003). For geometrical studies of the coordination mode of the nitrate anion, see: Kleywegt et al. (1985); Dowling et al. (1996).

S2. Experimental

15 cm³ of a 0.50 M methanolic solution of 2,2'-bipyridine was added to 20 cm³ of an aqueous solution of K₂CrO₄ (0.25 M). After 15 min of mixing, 10 cm³ of an 0.25 M aqueous solution of cobalt nitrate was added dropwise. This mixture of [Co²⁺–2,2'-bipyridine–CrO₄^2-] reagents in a 1:3:2 molar ratio was slowly evaporated at room temperature. After 14 days orange crystals of [Co(bpy)₃](CrO₄)_0.5.NO₃.7H₂O were obtained. The crystals were filtered off and the filtrate was left to stand. After 30 days pink prismatic crystals of the title compound were isolated.

S3. Refinement

All the hydrogen atoms were visible on difference maps and were refined with isotropic displacement parameters correlated with the anisotropic displacement parameters of the atoms to which they were bonded [C—H 0.93 (2) Å and U_iso(H) = 1.2U_eq(C)]. The positions of hydrogen atoms in the hydroxide ion and water molecules were determined from difference maps and were not refined [U_iso(H) = 1.5U_eq(O)].

Computing details

Data collection: CrysAlis CCD (Oxford Diffraction, 2007); cell refinement: CrysAlis RED (Oxford Diffraction, 2007); data reduction: CrysAlis RED (Oxford Diffraction, 2007; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Brandenburg, 2005); software used to prepare material for publication: publCIF (Westrip, 2007).

Figures

	Fig. 1. A view of [Co(bpy)2(NO3-O,O')]^+ cation, showing the atom numbering scheme of the asymmetric unit. Displacement ellipsoids are shown at the 50% probability level.
	Fig. 2. The hydrogen bonding network of (I) viewed along the c axis. Hydrogen bonds are indicated by dashed lines.

bis(2,2'-bipyridine)(nitrato-κ²O,O')cobalt(III) hydroxide nitrate tetrahydrate

Crystal data

[Co(NO3)(C10H8N2)2](OH)(NO3)·4H2O	F(000) = 1208
Mr = 584.39	Dx = 1.562 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 2212 reflections
a = 10.949 (2) Å	θ = 2.9–26.4°
b = 16.047 (3) Å	µ = 0.76 mm^−1
c = 14.456 (3) Å	T = 298 K
β = 101.92 (3)°	Prism, pink
V = 2485.1 (9) Å^3	0.38 × 0.25 × 0.21 mm
Z = 4

Data collection

KUMA KM-4 with CCD area detector diffractometer	2529 independent reflections
Radiation source: fine-focus sealed tube	2212 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.035
Detector resolution: 1024x1024 with blocks 2x2, 33.133pixel/mm pixels mm^-1	θmax = 26.4°, θmin = 2.9°
ω–scan	h = −13→13
Absorption correction: numerical (CrysAlis RED; Oxford Diffraction, 2007)	k = −19→20
Tmin = 0.847, Tmax = 0.930	l = −18→16
13043 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.043	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.123	H-atom parameters constrained
S = 1.06	w = 1/[σ^2(Fo^2) + (0.0763P)^2 + 1.6632P] where P = (Fo^2 + 2Fc^2)/3
2529 reflections	(Δ/σ)max < 0.001
175 parameters	Δρmax = 0.34 e Å^−3
0 restraints	Δρmin = −0.54 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
Co1	0.5000	0.50622 (2)	0.2500	0.03378 (17)
N11	0.5000	0.6494 (2)	0.2500	0.0744 (11)
O11	0.5000	0.72623 (19)	0.2500	0.1021 (13)
O12	0.55680 (17)	0.60295 (11)	0.19693 (12)	0.0486 (4)
N21	0.5000	0.1667 (3)	0.2500	0.0739 (10)
O21	0.5000	0.2402 (3)	0.2500	0.177 (3)
O22	0.5834 (4)	0.1293 (3)	0.3002 (3)	0.1659 (18)
N1	0.56282 (17)	0.42330 (12)	0.17425 (12)	0.0374 (4)
N2	0.35747 (19)	0.50549 (11)	0.14648 (13)	0.0361 (4)
C1	0.6699 (2)	0.38072 (17)	0.19718 (18)	0.0497 (6)
H1	0.7232	0.3913	0.2549	0.060*
C2	0.7033 (3)	0.3220 (2)	0.1382 (2)	0.0639 (8)
H2	0.7784	0.2934	0.1557	0.077*
C3	0.6250 (3)	0.30562 (19)	0.0530 (2)	0.0629 (7)
H3	0.6459	0.2652	0.0128	0.075*
C4	0.5152 (2)	0.34973 (17)	0.02769 (18)	0.0508 (6)
H4	0.4615	0.3400	−0.0301	0.061*
C5	0.2822 (2)	0.45824 (17)	−0.01124 (16)	0.0495 (6)
H5	0.2927	0.4256	−0.0622	0.059*
C6	0.1773 (3)	0.50778 (17)	−0.0174 (2)	0.0571 (7)
H6	0.1169	0.5093	−0.0730	0.068*
C7	0.1630 (2)	0.55457 (18)	0.0591 (2)	0.0572 (7)
H7	0.0924	0.5874	0.0562	0.069*
C8	0.2546 (2)	0.55237 (16)	0.14060 (18)	0.0486 (6)
H8	0.2448	0.5840	0.1925	0.058*
C9	0.4859 (2)	0.40857 (14)	0.08920 (14)	0.0380 (5)
C10	0.3712 (2)	0.45814 (14)	0.07220 (14)	0.0382 (5)
O1	0.2572 (3)	0.2652 (2)	0.0904 (3)	0.1321 (12)
H11	0.3083	0.2320	0.1342	0.198*
H12	0.1874	0.2802	0.1126	0.198*
O2	0.0487 (4)	0.33863 (18)	0.1216 (2)	0.1137 (10)
H21	0.0504	0.2873	0.1485	0.171*
H22	0.0588	0.3895	0.1520	0.171*
O3	0.0000	0.4538 (3)	0.2500	0.1300 (18)
H31	0.0000	0.5172	0.2500	0.195*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Co1	0.0356 (3)	0.0405 (3)	0.0229 (2)	0.000	0.00068 (16)	0.000
N11	0.080 (3)	0.055 (2)	0.075 (2)	0.000	−0.014 (2)	0.000
O11	0.129 (3)	0.0345 (16)	0.133 (3)	0.000	0.004 (3)	0.000
O12	0.0555 (10)	0.0477 (9)	0.0398 (9)	−0.0063 (8)	0.0033 (7)	0.0071 (7)
N21	0.086 (3)	0.063 (2)	0.075 (3)	0.000	0.022 (2)	0.000
O21	0.257 (9)	0.067 (3)	0.218 (7)	0.000	0.078 (7)	0.000
O22	0.161 (4)	0.161 (4)	0.147 (4)	0.060 (3)	−0.033 (3)	0.016 (3)
N1	0.0374 (9)	0.0447 (10)	0.0286 (8)	−0.0001 (7)	0.0031 (7)	−0.0012 (7)
N2	0.0364 (10)	0.0425 (10)	0.0274 (9)	0.0009 (7)	0.0020 (8)	0.0033 (7)
C1	0.0428 (13)	0.0601 (15)	0.0439 (13)	0.0087 (11)	0.0033 (10)	−0.0034 (11)
C2	0.0544 (16)	0.0712 (19)	0.0656 (18)	0.0173 (14)	0.0112 (13)	−0.0103 (14)
C3	0.0657 (18)	0.0674 (18)	0.0578 (16)	0.0080 (14)	0.0179 (14)	−0.0198 (14)
C4	0.0560 (15)	0.0588 (15)	0.0371 (11)	−0.0078 (11)	0.0089 (10)	−0.0112 (11)
C5	0.0537 (15)	0.0549 (15)	0.0333 (12)	−0.0088 (11)	−0.0064 (10)	0.0003 (10)
C6	0.0502 (16)	0.0656 (17)	0.0439 (15)	−0.0060 (12)	−0.0168 (12)	0.0080 (11)
C7	0.0414 (13)	0.0614 (16)	0.0617 (16)	0.0056 (11)	−0.0054 (12)	0.0104 (13)
C8	0.0435 (13)	0.0547 (14)	0.0452 (13)	0.0056 (11)	0.0035 (10)	0.0020 (11)
C9	0.0422 (12)	0.0436 (12)	0.0272 (10)	−0.0063 (9)	0.0051 (9)	0.0002 (8)
C10	0.0438 (12)	0.0398 (12)	0.0278 (10)	−0.0068 (9)	0.0003 (9)	0.0033 (8)
O1	0.101 (2)	0.135 (3)	0.147 (3)	0.003 (2)	−0.004 (2)	0.015 (2)
O2	0.139 (3)	0.094 (2)	0.105 (2)	0.0196 (19)	0.017 (2)	0.0046 (16)
O3	0.191 (5)	0.076 (3)	0.106 (3)	0.000	−0.008 (3)	0.000

Geometric parameters (Å, º)

Co1—O12^i	1.8924 (17)	C2—H2	0.9300
Co1—O12	1.8924 (17)	C3—C4	1.378 (4)
Co1—N2^i	1.926 (2)	C3—H3	0.9300
Co1—N2	1.926 (2)	C4—C9	1.379 (3)
Co1—N1^i	1.9374 (19)	C4—H4	0.9300
Co1—N1	1.9374 (19)	C5—C6	1.384 (4)
Co1—N11	2.297 (4)	C5—C10	1.385 (3)
N11—O11	1.233 (4)	C5—H5	0.9300
N11—O12	1.314 (3)	C6—C7	1.372 (4)
N11—O12^i	1.314 (3)	C6—H6	0.9300
N21—O21	1.180 (6)	C7—C8	1.380 (4)
N21—O22^i	1.202 (4)	C7—H7	0.9300
N21—O22	1.202 (4)	C8—H8	0.9300
N1—C1	1.338 (3)	C9—C10	1.464 (3)
N1—C9	1.360 (3)	O1—H11	0.9218
N2—C8	1.342 (3)	O1—H12	0.9194
N2—C10	1.349 (3)	O2—H21	0.9100
C1—C2	1.371 (4)	O2—H22	0.9225
C1—H1	0.9300	O3—H31	1.0180
C2—C3	1.372 (4)
O12^i—Co1—O12	69.80 (12)	C8—N2—Co1	125.47 (17)
O12^i—Co1—N2^i	88.36 (7)	C10—N2—Co1	114.60 (15)
O12—Co1—N2^i	92.21 (8)	N1—C1—C2	122.0 (2)
O12—Co1—N2	88.36 (7)	N1—C1—H1	119.0
O12^i—Co1—N2	92.21 (7)	C2—C1—H1	119.0
O12—Co1—N1^i	167.72 (8)	C1—C2—C3	119.5 (3)
O12—Co1—N1	98.59 (8)	C1—C2—H2	120.3
N2—Co1—N1	83.22 (8)	C3—C2—H2	120.3
N2—Co1—N1^i	96.30 (8)	C2—C3—C4	119.3 (2)
N2^i—Co1—N2	179.30 (10)	C2—C3—H3	120.4
O12^i—Co1—N1^i	98.59 (8)	C4—C3—H3	120.4
N2^i—Co1—N1^i	83.22 (8)	C3—C4—C9	119.1 (2)
O12^i—Co1—N1	167.72 (8)	C3—C4—H4	120.4
N2^i—Co1—N1	96.30 (8)	C9—C4—H4	120.4
N1^i—Co1—N1	93.25 (11)	C6—C5—C10	118.8 (2)
O12^i—Co1—N11	34.90 (6)	C6—C5—H5	120.6
O12—Co1—N11	34.90 (6)	C10—C5—H5	120.6
N2^i—Co1—N11	90.35 (5)	C7—C6—C5	119.6 (2)
N2—Co1—N11	90.35 (5)	C7—C6—H6	120.2
N1^i—Co1—N11	133.38 (6)	C5—C6—H6	120.2
N1—Co1—N11	133.38 (6)	C6—C7—C8	119.3 (3)
O11—N11—O12	124.54 (15)	C6—C7—H7	120.3
O11—N11—O12^i	124.54 (15)	C8—C7—H7	120.3
O12—N11—O12^i	110.9 (3)	N2—C8—C7	121.4 (2)
O11—N11—Co1	180.0	N2—C8—H8	119.3
O12—N11—Co1	55.46 (15)	C7—C8—H8	119.3
O12^i—N11—Co1	55.46 (15)	N1—C9—C4	121.3 (2)
N11—O12—Co1	89.64 (17)	N1—C9—C10	114.01 (19)
O21—N21—O22^i	119.9 (3)	C4—C9—C10	124.7 (2)
O21—N21—O22	119.9 (3)	N2—C10—C5	121.2 (2)
O22^i—N21—O22	120.2 (6)	N2—C10—C9	113.90 (18)
C1—N1—C9	118.8 (2)	C5—C10—C9	124.9 (2)
C1—N1—Co1	127.28 (16)	H11—O1—H12	110.0
C9—N1—Co1	113.87 (15)	H21—O2—H22	127.5
C8—N2—C10	119.7 (2)
O12^i—Co1—N11—O12	180.0	N11—Co1—N2—C8	−46.18 (19)
N2^i—Co1—N11—O12	93.37 (11)	O12^i—Co1—N2—C10	162.94 (16)
N2—Co1—N11—O12	−86.63 (11)	O12—Co1—N2—C10	93.23 (16)
N1^i—Co1—N11—O12	174.35 (11)	N1^i—Co1—N2—C10	−98.16 (16)
N1—Co1—N11—O12	−5.65 (11)	N1—Co1—N2—C10	−5.62 (15)
O12—Co1—N11—O12^i	180.000 (1)	N11—Co1—N2—C10	128.08 (15)
N2^i—Co1—N11—O12^i	−86.63 (11)	C9—N1—C1—C2	−1.0 (4)
N2—Co1—N11—O12^i	93.37 (11)	Co1—N1—C1—C2	178.6 (2)
N1^i—Co1—N11—O12^i	−5.65 (11)	N1—C1—C2—C3	−0.3 (5)
N1—Co1—N11—O12^i	174.35 (11)	C1—C2—C3—C4	1.1 (5)
O11—N11—O12—Co1	180.0	C2—C3—C4—C9	−0.8 (4)
O12^i—N11—O12—Co1	0.0	C10—C5—C6—C7	−0.8 (4)
O12^i—Co1—O12—N11	0.0	C5—C6—C7—C8	1.0 (4)
N2^i—Co1—O12—N11	−87.44 (9)	C10—N2—C8—C7	−1.3 (4)
N2—Co1—O12—N11	92.96 (9)	Co1—N2—C8—C7	172.68 (19)
N1^i—Co1—O12—N11	−19.6 (4)	C6—C7—C8—N2	0.1 (4)
N1—Co1—O12—N11	175.85 (8)	C1—N1—C9—C4	1.3 (3)
O12^i—Co1—N1—C1	114.8 (3)	Co1—N1—C9—C4	−178.29 (18)
O12—Co1—N1—C1	96.2 (2)	C1—N1—C9—C10	179.5 (2)
N2^i—Co1—N1—C1	2.9 (2)	Co1—N1—C9—C10	−0.1 (2)
N2—Co1—N1—C1	−176.5 (2)	C3—C4—C9—N1	−0.5 (4)
N1^i—Co1—N1—C1	−80.6 (2)	C3—C4—C9—C10	−178.4 (2)
N11—Co1—N1—C1	99.4 (2)	C8—N2—C10—C5	1.4 (3)
O12^i—Co1—N1—C9	−65.6 (4)	Co1—N2—C10—C5	−173.18 (17)
O12—Co1—N1—C9	−84.26 (16)	C8—N2—C10—C9	−178.4 (2)
N2^i—Co1—N1—C9	−177.47 (15)	Co1—N2—C10—C9	7.0 (2)
N2—Co1—N1—C9	3.04 (15)	C6—C5—C10—N2	−0.4 (4)
N1^i—Co1—N1—C9	99.00 (16)	C6—C5—C10—C9	179.5 (2)
N11—Co1—N1—C9	−81.00 (16)	N1—C9—C10—N2	−4.4 (3)
O12^i—Co1—N2—C8	−11.3 (2)	C4—C9—C10—N2	173.6 (2)
O12—Co1—N2—C8	−81.0 (2)	N1—C9—C10—C5	175.7 (2)
N1^i—Co1—N2—C8	87.6 (2)	C4—C9—C10—C5	−6.2 (4)
N1—Co1—N2—C8	−179.9 (2)

Symmetry code: (i) −x+1, y, −z+1/2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H11···O22^i	0.92	2.14	3.027 (6)	162.4
O1—H11···O21	0.92	2.40	3.165 (4)	139.9
O1—H12···O2	0.92	1.81	2.689 (5)	158.4
O2—H21···O11^ii	0.91	1.94	2.718 (4)	142.9
O2—H22···O3	0.92	1.97	2.748 (4)	141.5
O3—H31···O22^iii	1.02	2.08	3.004 (6)	150
O3—H31···O22^iv	1.02	2.08	3.004 (6)	150

Symmetry codes: (i) −x+1, y, −z+1/2; (ii) x−1/2, y−1/2, z; (iii) x−1/2, y+1/2, z; (iv) −x+1/2, y+1/2, −z+1/2.