Crystal structure of 4-(di­methyl­amino)­pyridinium cis-di­aqua­bis­(oxalato-κ2O,O′)ferrate(III) hemihydrate

Djomo, E.D.; Capet, F.; Nenwa, J.; Bélombé, M.M.; Foulon, M.

doi:10.1107/S2056989015013213

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ISSN: 2056-9890

Volume 71| Part 8| August 2015| Pages 934-936

https://doi.org/10.1107/S2056989015013213

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Crystal structure of 4-(dimethylamino)pyridinium cis-diaquabis(oxalato-κ²O,O′)ferrate(III) hemihydrate

Edith Dimitri Djomo,^a Frédéric Capet,^b Justin Nenwa,^a ^* Michel M. Bélombé ^a and Michel Foulon ^c

^aDepartment of Inorganic Chemistry, University of Yaounde 1, POB 812 Yaounde, Cameroon, ^bUnité de Catalyse et de Chimie du Solide, UMR 8181, École Nationale Supérieure de Chimie de Lille, Université Lille-1, 59650 Villeneuve d'Ascq Cedex, France, and ^cUFR de Physique, Université Lille-1, 59650 Villeneuve d'Ascq Cedex, France
^*Correspondence e-mail: jnenwa@yahoo.fr

Edited by A. Van der Lee, Université de Montpellier II, France (Received 22 June 2015; accepted 9 July 2015; online 15 July 2015)

The Fe^III ions in the hybrid title salt, (C₇H₁₁N₂)[Fe(C₂O₄)₂(H₂O)₂]·0.5H₂O, show a distorted octahedral coordination environment, with four O atoms from two chelating oxalate dianions and two O atoms from two cis aqua ligands. The average Fe—O(oxalate) bond length [2.00 (2) Å] is shorter than the average Fe—O(water) bond length [2.027 (19) Å]. The ionic components are connected via intermolecular N—H⋯O and O—H⋯O hydrogen bonds into a three-dimensional network.

Keywords: crystal structure; 4-(dimethylamino)pyridine; bis(oxalate)ferrate(III) complex; hybrid salt; hydrogen bonding.

CCDC reference: 1400489

1. Chemical context

Over the past years, the design and synthesis of organic–inorganic hybrid salts have attracted much attention not only because of their fascinating network topologies, but also to obtain a better understanding of the correlations between their structural and physical properties (Bloomquist et al., 1981 ; Geiser et al., 1987 ; Pardo et al., 2012 ). In this context, the bis-oxalato complexes of transition metals, [M^III(C₂O₄)₂(H₂O)₂]⁻, are extremely versatile building blocks for the synthesis of organic–inorganic hybrid salts. Although several salts of general formula A[M^III(C₂O₄)₂(H₂O)₂]·xH₂O (A⁺ = aromatic iminium cation, 0≤x≤1) have been explored to date (Bélombé et al., 2009 ; Nenwa et al., 2010 ; Chérif et al., 2011 ; Chérif, Abdelhak et al., 2012 ; Chérif, Zid et al., 2012 ; Nenwa et al., 2012a ,b ; Dridi et al., 2013 ; Bebga et al., 2013 ), the predictable and consistent formation of networks is still in its infancy. In most cases, the network topologies are influenced by the organic counter-cations, metal coordination spheres, pH values, guest molecules and the crystallization solvent. So far, most of the self-assembly processes involving anionic species, [M^III(C₂O₄)₂(H₂O)₂]⁻, and aromatic iminium cations have led to salts with trans-diaquabis(oxalate)metallate(III) complex anions (Bélombé et al., 2009, Nenwa et al., 2010, 2012a; Chérif, Zid et al., 2012; Dridi et al., 2013; Gouet et al., 2013 ). The cis configuration of the complex anion [M^III(C₂O₄)₂(H₂O)₂]⁻ is less common in the literature, and has been observed in salts with 2-amino-5-chloropyridinium (Chérif, Abdelhak et al., 2012) or with pyridinium (Nenwa et al., 2012b) as aromatic iminium cations. In this work, we extend this family of salts involving the complex anion [M^III(C₂O₄)₂(H₂O)₂]⁻ in its cis-configuration by reporting the structural characterization of the title compound with composition (C₇H₁₁N₂)[Fe(C₂O₄)₂(H₂O)₂]·0.5H₂O.

2. Structural commentary

The asymmetric unit of the title compound shown in Fig. 1 consists of one protonated 4-(dimethylamino)pyridine molecule (C₇H₁₁N₂)⁺, one anionic complex [Fe(C₂O₄)₂(H₂O)₂]⁻ in a cis-aqua configuration and one-half solvent water molecule. Atom O3W of this water molecule of solvation lies on a crystallographic twofold rotation axis. The main geometric parameters of the (C₇H₁₁N₂)⁺ cation are in agreement with those found in a similar salt with the same cationic entity (Nenwa et al., 2010). The iron(III) site in the complex anion has a distorted octahedral coordination environment built up by two O atoms (O1W, O2W) from two cis-aqua ligands and four O atoms (O3, O4, O5, O6) from two chelating oxalate dianions. The average Fe—O_(oxalate) bond length [2.00 (2) Å] is shorter than the average Fe—O_(water) bond length [2.027 (19) Å]. The bond lengths in the [Fe(C₂O₄)₂(H₂O)₂]⁻ anion are similar to those observed in homologous compounds with a cis-aqua configuration of the [M^III(C₂O₄)₂(H₂O)₂]⁻ anionic units (Chérif, Abdelhak et al., 2012; Nenwa et al., 2012b).

Figure 1
View of the molecular components of (I)

, showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.

3. Supramolecular features

Within the crystal packing, the charged components are connected by an extensive hydrogen-bonding network. Hydrogen bonds of the type O—H⋯O involving coordinating water molecules as donor groups and auxilliary O atoms of the oxalate dianions as acceptor groups interconnect neighboring [Fe(C₂O₄)₂(H₂O)₂]⁻ anionic units (Table 1, Fig. 2). Together with the relatively weaker N—H⋯O hydrogen bonds of the protonated imine N atoms of the 4-(dimethylamino)pyridine molecules to the oxalate dianions, a three-dimensional framework is formed (Table 1, Fig. 3).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1W—H1WA⋯O2ⁱ	0.81 (2)	1.94 (2)	2.720 (3)	162 (4)
O1W—H1WB⋯O7ⁱⁱ	0.77 (2)	2.40 (3)	2.988 (3)	134 (4)
O1W—H1WB⋯O3Wⁱⁱⁱ	0.77 (2)	2.34 (3)	2.9699 (19)	139 (4)
O2W—H2WA⋯O8^iv	0.82 (2)	1.84 (2)	2.664 (3)	176 (3)
O2W—H2WB⋯O1^v	0.83 (2)	1.88 (2)	2.702 (2)	171 (3)
N1—H1⋯O1^v	0.86	2.11	2.931 (3)	160
N1—H1⋯O2^v	0.86	2.46	3.043 (3)	125
O3W—H3W⋯O7^vi	0.84 (2)	2.36 (5)	3.040 (2)	138 (6)
O3W—H3W⋯O8^vi	0.84 (2)	2.09 (5)	2.782 (3)	140 (6)
Symmetry codes: (i) $[-x+{\script{1\over 2}}, -y+{\script{5\over 2}}, -z+{\script{1\over 2}}]$ ; (ii) -x+1, -y+2, -z+1; (iii) x, y+1, z; (iv) $[x-{\script{1\over 2}}, -y+2, z]$ ; (v) $[-x+{\script{1\over 2}}, -y+{\script{3\over 2}}, -z+{\script{1\over 2}}]$ ; (vi) -x+1, -y+1, -z+1.

Figure 2
The environment of the [Fe(C₂O₄)₂(H₂O)₂]⁻ octahedron. Dashed lines denote hydrogen bonds.

Figure 3
A (100) projection of the crystal structure of the title compound. Hydrogen bonds are shown as dashed lines.

4. Synthesis and crystallization

The salt Fe(NO₃)₃·6H₂O (1 mmol, 400 mg) was dissolved in 20 ml of water, leading to a yellowish solution. This solution was added in successive small portions in 30 ml of a mixture of oxalic acid (2 mmol, 253 mg) and 4-(dimethylamino)pyridine (1 mmol, 122 mg) with stirring at 323 K for 2 h. The resulting greenish solution was left at room temperature; crystals suitable for X-ray diffraction were obtained after two weeks upon slow evaporation.

5. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. H atoms bonded to C and N atoms were placed at geometrically calculated positions and refined using a riding model. C—H distances were fixed at 0.93 and 0.96 Å for aromatic and methyl C atoms, respectively. The N—H distance was fixed at 0.86 Å. The U_iso(H) values were equal to 1.2 and 1.5 times U_eq of the corresponding C(sp²) and C(sp³) atoms, and 1.2 times U_eq of the N atom. All water H atoms were located from a difference-Fourier map and refined with soft restraints on the O—H and H⋯H distances [O—H = 0.82 (2) and H⋯H = 1.30 (4) Å] with U_iso(H) = 1.5U_eq(O).

Table 2
Experimental details

Crystal data
Chemical formula	(C₇H₁₁N₂)[Fe(C₂O₄)₂(H₂O)₂]·0.5H₂O
M_r	800.22
Crystal system, space group	Monoclinic, I2/a
Temperature (K)	296
a, b, c (Å)	14.7960 (7), 10.4422 (4), 21.7751 (10)
β (°)	108.352 (3)
V (Å³)	3193.2 (2)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	1.00
Crystal size (mm)	0.26 × 0.22 × 0.13

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2014 )
T_min, T_max	0.679, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections	48070, 4880, 3435
R_int	0.044
(sin θ/λ)_max (Å⁻¹)	0.715

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.042, 0.123, 1.06
No. of reflections	4880
No. of parameters	239
No. of restraints	8
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.85, −0.58
Computer programs: APEX2 and SAINT (Bruker, 2014), SHELXS97 (Sheldrick, 2008 ), SHELXL2014 (Sheldrick, 2015 ), OLEX2 (Dolomanov et al., 2009 ), publCIF (Westrip, 2010 ) and PLATON (Spek, 2009 ).

Supporting information

CCDC reference: 1400489

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2056989015013213/vn2095sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989015013213/vn2095Isup2.hkl

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2014); cell refinement: SAINT (Bruker, 2014); data reduction: SAINT (Bruker, 2014); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009), publCIF (Westrip, 2010) and PLATON (Spek, 2009).

4-(Dimethylamino)pyridinium cis-diaquabis(oxalato-κ²O,O')ferrate(III) hemihydrate top

Crystal data top

(C₇H₁₁N₂)[Fe(C₂O₄)₂(H₂O)₂]·0.5H₂O	F(000) = 1648
M_r = 800.22	D_x = 1.665 Mg m⁻³
Monoclinic, I2/a	Mo Kα radiation, λ = 0.71073 Å
a = 14.7960 (7) Å	Cell parameters from 9923 reflections
b = 10.4422 (4) Å	θ = 2.2–27.3°
c = 21.7751 (10) Å	µ = 1.00 mm⁻¹
β = 108.352 (3)°	T = 296 K
V = 3193.2 (2) Å³	Irregular, yellow
Z = 4	0.26 × 0.22 × 0.13 mm

Data collection top

Bruker APEXII CCD diffractometer	3435 reflections with I > 2σ(I)
Radiation source: sealed X-ray tube	R_int = 0.044
φ and ω scans	θ_max = 30.6°, θ_min = 2.8°
Absorption correction: multi-scan (SADABS2014; Bruker, 2014)	h = −21→21
T_min = 0.679, T_max = 0.746	k = −14→14
48070 measured reflections	l = −31→31
4880 independent reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.042	Hydrogen site location: mixed
wR(F²) = 0.123	H atoms treated by a mixture of independent and constrained refinement
S = 1.06	w = 1/[σ²(F_o²) + (0.0528P)² + 5.0524P] where P = (F_o² + 2F_c²)/3
4880 reflections	(Δ/σ)_max = 0.001
239 parameters	Δρ_max = 0.85 e Å⁻³
8 restraints	Δρ_min = −0.58 e Å⁻³

Special details top

Experimental. Absorption correction: SADABS-2014/3 (Bruker, 2014) was used for absorption correction. wR2(int) was 0.0678 before and 0.0491 after correction. The Ratio of minimum to maximum transmission is 0.9094. The λ/2 correction factor is 0.00150.

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Fe1	0.33846 (2)	0.99760 (3)	0.33390 (2)	0.02994 (10)
O1	0.27198 (13)	0.84143 (16)	0.15711 (7)	0.0393 (4)
O1W	0.31148 (18)	1.14895 (18)	0.38270 (9)	0.0511 (5)
H1WA	0.287 (3)	1.216 (2)	0.3669 (16)	0.077*
H1WB	0.321 (3)	1.132 (4)	0.4186 (10)	0.077*
O2	0.23808 (16)	1.10293 (17)	0.14845 (8)	0.0524 (5)
O2W	0.21255 (12)	0.91604 (16)	0.33264 (9)	0.0381 (4)
H2WA	0.187 (2)	0.941 (3)	0.3590 (13)	0.057*
H2WB	0.223 (2)	0.8379 (17)	0.3394 (15)	0.057*
O3	0.33473 (12)	0.86776 (14)	0.26407 (7)	0.0343 (3)
O4	0.29136 (13)	1.10922 (15)	0.25610 (7)	0.0389 (4)
O5	0.39926 (12)	0.89364 (16)	0.41206 (8)	0.0398 (4)
O6	0.47565 (13)	1.04452 (18)	0.34780 (8)	0.0408 (4)
O7	0.53967 (14)	0.85689 (19)	0.48747 (9)	0.0504 (5)
O8	0.62163 (14)	1.0053 (2)	0.41370 (12)	0.0625 (6)
C1	0.29387 (15)	0.9073 (2)	0.20675 (10)	0.0293 (4)
C2	0.27184 (17)	1.0531 (2)	0.20161 (10)	0.0338 (5)
C3	0.49036 (17)	0.9055 (2)	0.43727 (11)	0.0335 (5)
C4	0.53485 (18)	0.9927 (2)	0.39683 (12)	0.0377 (5)
N1	0.34280 (18)	0.5649 (3)	0.47049 (11)	0.0564 (6)
H1	0.3107	0.5735	0.4302	0.068*
N2	0.49507 (17)	0.5221 (2)	0.66339 (10)	0.0442 (5)
C5	0.44607 (18)	0.5376 (2)	0.60033 (11)	0.0371 (5)
C6	0.4118 (3)	0.4314 (3)	0.55903 (14)	0.0609 (9)
H6	0.4241	0.3488	0.5756	0.073*
C7	0.3617 (3)	0.4484 (4)	0.49606 (15)	0.0683 (10)
H7	0.3400	0.3771	0.4700	0.082*
C8	0.3735 (2)	0.6686 (3)	0.50711 (14)	0.0518 (7)
H8	0.3599	0.7493	0.4885	0.062*
C9	0.42434 (19)	0.6587 (3)	0.57107 (13)	0.0438 (6)
H9	0.4448	0.7324	0.5955	0.053*
C10	0.5313 (2)	0.6307 (3)	0.70562 (14)	0.0521 (7)
H10A	0.5788	0.6742	0.6919	0.078*
H10B	0.5591	0.6011	0.7493	0.078*
H10C	0.4801	0.6885	0.7036	0.078*
C11	0.5175 (3)	0.3955 (3)	0.69141 (16)	0.0704 (10)
H11A	0.4600	0.3467	0.6833	0.106*
H11B	0.5480	0.4030	0.7372	0.106*
H11C	0.5596	0.3530	0.6723	0.106*
O3W	0.2500	0.1564 (4)	0.5000	0.117 (2)
H3W	0.302 (3)	0.115 (5)	0.512 (3)	0.176*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Fe1	0.03909 (18)	0.02585 (16)	0.02228 (15)	−0.00039 (12)	0.00595 (11)	−0.00107 (11)
O1	0.0583 (11)	0.0306 (8)	0.0283 (8)	−0.0001 (7)	0.0126 (7)	−0.0071 (6)
O1W	0.0945 (16)	0.0285 (9)	0.0335 (9)	0.0046 (9)	0.0247 (10)	−0.0040 (7)
O2	0.0879 (15)	0.0359 (9)	0.0250 (8)	0.0134 (9)	0.0059 (9)	0.0014 (7)
O2W	0.0401 (9)	0.0323 (8)	0.0426 (9)	0.0015 (7)	0.0141 (7)	−0.0069 (7)
O3	0.0490 (10)	0.0253 (7)	0.0270 (7)	0.0055 (6)	0.0099 (7)	−0.0007 (6)
O4	0.0615 (11)	0.0244 (8)	0.0252 (7)	0.0070 (7)	0.0058 (7)	−0.0026 (6)
O5	0.0411 (9)	0.0398 (9)	0.0349 (8)	−0.0073 (7)	0.0070 (7)	0.0109 (7)
O6	0.0430 (9)	0.0422 (9)	0.0349 (9)	−0.0037 (7)	0.0089 (7)	0.0125 (7)
O7	0.0505 (11)	0.0505 (11)	0.0431 (10)	0.0023 (8)	0.0047 (8)	0.0186 (8)
O8	0.0355 (10)	0.0863 (17)	0.0660 (14)	0.0012 (10)	0.0163 (9)	0.0341 (12)
C1	0.0349 (11)	0.0266 (10)	0.0281 (10)	0.0003 (8)	0.0121 (8)	−0.0021 (8)
C2	0.0442 (12)	0.0283 (10)	0.0273 (10)	0.0042 (9)	0.0088 (9)	−0.0016 (8)
C3	0.0412 (12)	0.0280 (10)	0.0308 (10)	0.0008 (9)	0.0106 (9)	0.0051 (8)
C4	0.0377 (12)	0.0379 (12)	0.0390 (12)	0.0001 (9)	0.0140 (10)	0.0058 (10)
N1	0.0565 (14)	0.0824 (19)	0.0260 (10)	0.0018 (13)	0.0071 (10)	0.0052 (11)
N2	0.0548 (13)	0.0377 (11)	0.0308 (10)	0.0045 (9)	−0.0001 (9)	−0.0004 (8)
C5	0.0457 (13)	0.0341 (11)	0.0293 (11)	0.0038 (10)	0.0086 (9)	−0.0016 (9)
C6	0.090 (2)	0.0377 (15)	0.0408 (14)	0.0106 (14)	0.0006 (14)	−0.0075 (12)
C7	0.088 (3)	0.063 (2)	0.0414 (16)	0.0035 (18)	0.0019 (15)	−0.0201 (15)
C8	0.0521 (16)	0.0561 (17)	0.0468 (15)	−0.0012 (13)	0.0152 (12)	0.0233 (13)
C9	0.0515 (15)	0.0350 (13)	0.0418 (13)	−0.0050 (10)	0.0101 (11)	0.0070 (10)
C10	0.0519 (16)	0.0573 (17)	0.0395 (13)	−0.0063 (13)	0.0032 (11)	−0.0116 (12)
C11	0.087 (2)	0.0517 (18)	0.0514 (17)	0.0136 (17)	−0.0089 (16)	0.0126 (14)
O3W	0.076 (3)	0.057 (2)	0.154 (4)	0.000	−0.056 (3)	0.000

Geometric parameters (Å, º) top

Fe1—O1W	2.0133 (18)	N1—C7	1.330 (5)
Fe1—O2W	2.0407 (18)	N1—C8	1.337 (4)
Fe1—O3	2.0250 (15)	N2—C5	1.345 (3)
Fe1—O4	1.9927 (16)	N2—C10	1.452 (3)
Fe1—O5	1.9799 (16)	N2—C11	1.450 (4)
Fe1—O6	2.0163 (18)	C5—C6	1.417 (4)
O1—C1	1.235 (3)	C5—C9	1.407 (3)
O1W—H1WA	0.809 (17)	C6—H6	0.9300
O1W—H1WB	0.771 (17)	C6—C7	1.349 (4)
O2—C2	1.223 (3)	C7—H7	0.9300
O2W—H2WA	0.824 (17)	C8—H8	0.9300
O2W—H2WB	0.834 (17)	C8—C9	1.363 (4)
O3—C1	1.272 (3)	C9—H9	0.9300
O4—C2	1.272 (3)	C10—H10A	0.9600
O5—C3	1.291 (3)	C10—H10B	0.9600
O6—C4	1.269 (3)	C10—H10C	0.9600
O7—C3	1.218 (3)	C11—H11A	0.9600
O8—C4	1.226 (3)	C11—H11B	0.9600
C1—C2	1.554 (3)	C11—H11C	0.9600
C3—C4	1.550 (3)	O3W—H3W	0.842 (19)
N1—H1	0.8600

O1W—Fe1—O2W	90.16 (8)	O8—C4—O6	125.9 (2)
O1W—Fe1—O3	163.51 (8)	O8—C4—C3	119.0 (2)
O1W—Fe1—O6	95.03 (9)	C7—N1—H1	119.9
O3—Fe1—O2W	84.35 (7)	C7—N1—C8	120.2 (2)
O4—Fe1—O1W	85.14 (7)	C8—N1—H1	119.9
O4—Fe1—O2W	99.16 (8)	C5—N2—C10	121.7 (2)
O4—Fe1—O3	80.42 (6)	C5—N2—C11	121.2 (2)
O4—Fe1—O6	92.95 (7)	C11—N2—C10	117.1 (2)
O5—Fe1—O1W	95.09 (8)	N2—C5—C6	121.6 (2)
O5—Fe1—O2W	87.05 (7)	N2—C5—C9	122.9 (2)
O5—Fe1—O3	100.13 (7)	C9—C5—C6	115.5 (2)
O5—Fe1—O4	173.78 (7)	C5—C6—H6	119.5
O5—Fe1—O6	80.84 (7)	C7—C6—C5	121.0 (3)
O6—Fe1—O2W	167.19 (7)	C7—C6—H6	119.5
O6—Fe1—O3	93.64 (7)	N1—C7—C6	121.4 (3)
Fe1—O1W—H1WA	126 (3)	N1—C7—H7	119.3
Fe1—O1W—H1WB	110 (3)	C6—C7—H7	119.3
H1WA—O1W—H1WB	123 (3)	N1—C8—H8	119.2
Fe1—O2W—H2WA	118 (2)	N1—C8—C9	121.5 (3)
Fe1—O2W—H2WB	107 (2)	C9—C8—H8	119.2
H2WA—O2W—H2WB	107 (3)	C5—C9—H9	119.8
C1—O3—Fe1	114.30 (13)	C8—C9—C5	120.3 (3)
C2—O4—Fe1	116.08 (14)	C8—C9—H9	119.8
C3—O5—Fe1	116.33 (14)	N2—C10—H10A	109.5
C4—O6—Fe1	114.72 (15)	N2—C10—H10B	109.5
O1—C1—O3	126.2 (2)	N2—C10—H10C	109.5
O1—C1—C2	119.43 (19)	H10A—C10—H10B	109.5
O3—C1—C2	114.39 (17)	H10A—C10—H10C	109.5
O2—C2—O4	126.3 (2)	H10B—C10—H10C	109.5
O2—C2—C1	119.91 (19)	N2—C11—H11A	109.5
O4—C2—C1	113.77 (18)	N2—C11—H11B	109.5
O5—C3—C4	112.84 (19)	N2—C11—H11C	109.5
O7—C3—O5	126.3 (2)	H11A—C11—H11B	109.5
O7—C3—C4	120.9 (2)	H11A—C11—H11C	109.5
O6—C4—C3	115.1 (2)	H11B—C11—H11C	109.5

Fe1—O3—C1—O1	−170.06 (19)	O7—C3—C4—O6	−175.6 (2)
Fe1—O3—C1—C2	10.4 (2)	O7—C3—C4—O8	5.0 (4)
Fe1—O4—C2—O2	176.4 (2)	N1—C8—C9—C5	0.1 (4)
Fe1—O4—C2—C1	−3.0 (3)	N2—C5—C6—C7	179.1 (3)
Fe1—O5—C3—O7	174.7 (2)	N2—C5—C9—C8	−179.2 (3)
Fe1—O5—C3—C4	−4.7 (3)	C5—C6—C7—N1	0.1 (6)
Fe1—O6—C4—O8	178.3 (2)	C6—C5—C9—C8	0.0 (4)
Fe1—O6—C4—C3	−1.1 (3)	C7—N1—C8—C9	−0.2 (5)
O1—C1—C2—O2	−4.1 (4)	C8—N1—C7—C6	0.1 (5)
O1—C1—C2—O4	175.3 (2)	C9—C5—C6—C7	−0.2 (5)
O3—C1—C2—O2	175.4 (2)	C10—N2—C5—C6	179.2 (3)
O3—C1—C2—O4	−5.2 (3)	C10—N2—C5—C9	−1.6 (4)
O5—C3—C4—O6	3.8 (3)	C11—N2—C5—C6	1.9 (5)
O5—C3—C4—O8	−175.6 (2)	C11—N2—C5—C9	−178.8 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1WA···O2ⁱ	0.81 (2)	1.94 (2)	2.720 (3)	162 (4)
O1W—H1WB···O7ⁱⁱ	0.77 (2)	2.40 (3)	2.988 (3)	134 (4)
O1W—H1WB···O3Wⁱⁱⁱ	0.77 (2)	2.34 (3)	2.9699 (19)	139 (4)
O2W—H2WA···O8^iv	0.82 (2)	1.84 (2)	2.664 (3)	176 (3)
O2W—H2WB···O1^v	0.83 (2)	1.88 (2)	2.702 (2)	171 (3)
N1—H1···O1^v	0.86	2.11	2.931 (3)	160
N1—H1···O2^v	0.86	2.46	3.043 (3)	125
O3W—H3W···O7^vi	0.84 (2)	2.36 (5)	3.040 (2)	138 (6)
O3W—H3W···O8^vi	0.84 (2)	2.09 (5)	2.782 (3)	140 (6)

Symmetry codes: (i) −x+1/2, −y+5/2, −z+1/2; (ii) −x+1, −y+2, −z+1; (iii) x, y+1, z; (iv) x−1/2, −y+2, z; (v) −x+1/2, −y+3/2, −z+1/2; (vi) −x+1, −y+1, −z+1.

Acknowledgements

The authors thank Professor Simeon Kouam Fogue (Higher Teacher Training College, Chemistry Department, University of Yaounde I) for the donation of 4-(dimethylamino)pyridine. The Fonds Européen de Développement Régional (FEDER), CNRS, Région Nord Pas-de-Calais and Ministère de l'Education Nationale de l'Enseignement Supérieur et de la Recherche are acknowledged for funding the X-ray diffractometers.

References

Bebga, G., Signé, M., Nenwa, J., Mbarki, M. & Fokwa, B. P. T. (2013). Acta Cryst. E69, m567. CSD CrossRef IUCr Journals Google Scholar
Bélombé, M. M., Nenwa, J. & Emmerling, F. (2009). Z. Kristallogr. New Cryst. Struct. 224,239–240. Google Scholar
Bloomquist, D. R., Hansen, J. J., Landee, C. P., Willett, R. D. & Buder, R. (1981). Inorg. Chem. 20, 3308–3314. CSD CrossRef CAS Web of Science Google Scholar
Bruker (2014). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Chérif, I., Abdelhak, J., Zid, M. F. & Driss, A. (2011). Acta Cryst. E67, m1648–m1649. Web of Science CSD CrossRef IUCr Journals Google Scholar
Chérif, I., Abdelhak, J., Zid, M. F. & Driss, A. (2012). Acta Cryst. E68, m824–m825. CSD CrossRef IUCr Journals Google Scholar
Chérif, I., Zid, M. F., El-Ghozzi, M. & Avignant, D. (2012). Acta Cryst. E68, m900–m901. CSD CrossRef IUCr Journals Google Scholar
Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339–341. Web of Science CrossRef CAS IUCr Journals Google Scholar
Dridi, R., Namouchi Cherni, S., Zid, M. F. & Driss, A. (2013). Acta Cryst. E69, m489–m490. CSD CrossRef CAS IUCr Journals Google Scholar
Geiser, U., Ramakrishna, B. L., Willett, R. D., Hulsbergen, F. B. & Reedijk, J. (1987). Inorg. Chem. 26, 3750–3756. CSD CrossRef CAS Web of Science Google Scholar
Gouet et al. (2013). Please supply full reference. Google Scholar
Nenwa, J., Bebga, G., Martin, S., Bélombé, M. M., Mbarki, M. & Fokwa, B. P. T. (2012a). Acta Cryst. E68, m1325–m1326. CSD CrossRef IUCr Journals Google Scholar
Nenwa, J., Befolo, O., Gouet, B., Mbarki, M. & Fokwa, B. P. T. (2012b). Acta Cryst. E68, m1434. CSD CrossRef IUCr Journals Google Scholar
Nenwa, J., Belombe, M. M., Ngoune, J. & Fokwa, B. P. T. (2010). Acta Cryst. E66, m1410. Web of Science CSD CrossRef IUCr Journals Google Scholar
Pardo, E., Train, C., Boubekeur, K., Gontard, G., Cano, J., Lloret, F., Nakatani, K. & Verdaguer, M. (2012). Inorg. Chem. 51, 11582–11593. Web of Science CSD CrossRef CAS PubMed Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Sheldrick, G. M. (2015). Acta Cryst. C71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar
Westrip, S. P. (2010). J. Appl. Cryst. 43, 920–925. Web of Science CrossRef CAS IUCr Journals Google Scholar

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