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Acta Cryst. (2008). E64, m505-m506    [ doi:10.1107/S1600536808005540 ]

Diaquabis(4-chlorobenzoato-[kappa]O)bis(N,N-diethylnicotinamide-[kappa]N1)manganese(II)

T. Hökelek, N. Çaylak and H. Necefoglu

Abstract top

The title compound, [Mn(C7H4ClO2)2(C10H14N2O)2(H2O)2], is a monomeric complex with the MnII atom lying on an inversion center. It contains two 4-chlorobenzoate and two diethylnicotinamide ligands and two water molecules, all of which are monodentate. The four O atoms in the equatorial plane around the Mn atom form a slightly distorted square-planar arrangement, while the distorted octahedral geometry is completed by two N atoms in the axial positions. In the crystal structure, O-H...O hydrogen bonds link the molecules into an infinite chain.

Comment top

Transition metal complexes with biochemical molecules show interesting physical and/or chemical properties, through which they may find applications in biological systems (Antolini et al., 1982). The structural functions and coordination relationships of the arylcarboxylate ions in manganese(II) complexes of benzoic acid derivatives may be changed, depending on the nature and position of the substituted groups on the benzene ring, the nature of the additional ligand molecule or solvent, and the medium of the synthesis (Adiwidjaja et al., 1978; Amiraslanov et al., 1979; Antsyshkina et al., 1980; Nadzhafov et al., 1981; Shnulin et al., 1981).

N,N-Diethylnicotinamide (DENA) is an important respiratory stimulant. The structures of several complexes obtained by reacting divalent transition metal ions with DENA have been determined in our laboratory, including those of Cu2(DENA)2(C6H5COO)4, (II), (Hökelek et al., 1995), [Zn2(DENA)2(C7H5O3)4].2H2O, (III), (Hökelek & Necefoğlu, 1996), [Co(DENA)2(C7H5O3)2(H2O)2], (IV), (Hökelek & Necefoğlu, 1997), [Cu(DENA)2(C7H4NO4)2(H2O)2], (V), (Hökelek et al., 1997) and [Zn(DENA)2(C7H4FO2)2(H2O)2], (VI), (Hökelek et al., 2007). The structure determination of the title compound, (I), a manganese(II) complex with two chlorobenzoate (CB), two DENA ligands and two water molecules, was undertaken in order to determine the properties of the CB and DENA ligands and also to compare the results obtained with those reported previously.

Compound (I) is a monomeric complex, with the Mn atom lying on a center of symmetry. It contains two CB, two DENA ligands and two water molecules (Fig. 1). All ligands are monodentate. The four O atoms (O1, O4, and their symmetry-related atoms) in the equatorial plane around the Mn atom form a slightly distorted square-planar arrangement, while the slightly distorted octahedral coordination geometry is completed by the two N atoms of the DENA ligands in the axial positions (Table 1 and Fig. 1).

The near equality of the C1—O1 [1.256 (6) Å] and C1—O2 [1.245 (6) Å] bonds in the carboxylate group indicates a delocalized bonding arrangement, rather than localized single and double bonds, and may be compared with the corresponding distances: 1.259 (9) and 1.273 (9) Å in (II), 1.279 (4) and 1.246 (4) Å in (III), 1.251 (6) and 1.254 (7) Å in (IV), 1.278 (3) and 1.246 (3) Å in (V) and 1.265 (6) and 1.275 (6) Å in [Mn(C9H10NO2)2(H2O)4].2H2O, (VII), (Hökelek & Necefoğlu, 2007). This may be due to the intramolecular O—H···O hydrogen bond involving the carboxylate O atom (Table 2). In (I), the average Mn—O bond length is 2.173 (3) Å. The Mn atom is displaced out of the least-squares plane of the carboxylate group (O1/C1/O2) by 0.890 (1) Å; this is reported as 2.185 (4) and 1.365 (3) Å, respectively, in (VII). The dihedral angle between the planar carboxylate group and the benzene ring A (C2 to C7) is 3.0 (4)°, while that between rings A and B (N1/C8 to C12) is 81.0 (4)°.

As can be seen from the packing diagram (Fig. 2), the Mn atoms are located at the corners of the unit cell and the molecules of (I) are linked into infinite chains along the a-axis by intermolecular O—H···O hydrogen bonds (Table 2).

Related literature top

For general background, see: Adiwidjaja et al. (1978); Amiraslanov et al. (1979); Antolini et al. (1982); Antsyshkina et al. (1980); Nadzhafov et al. (1981); Shnulin et al. (1981). For related structures, see: Hökelek et al. (1995, 1997); Hökelek et al. (2007); Hökelek & Necefoğlu (1996, 1997, 2007).

Experimental top

The title compound was prepared by the reaction of Mn(NO3)2 (1.79 g, 10 mmol) in H2O (25 ml) and DENA (3.56 g, 20 mmol) in H2O (25 ml) with sodium p-chlorobenzoate (3.57 g, 20 mmol) in H2O (100 ml). The mixture was filtered and set aside to crystallize at ambient temperature for several days, giving colorless single crystals.

Refinement top

H atoms of the water molecule were located in a difference Fourier map and refined isotropically. The remaining H atoms were positioned geometrically and refined as riding atoms, with C—H = 0.93 (aromatic), 0.97 (methylene) and 0.96 Å (methyl) and with Uiso(H) = xUeq(C), where x = 1.0 for H atoms of C15 methyl, 1.5 for H atoms of C17 methyl, and 1.2 for other H atoms. The restrains on the C14—C15 bond length and O—H bond lengths and H—O—H bond angle of water molecule were applied. The highest residual electron density was found 0.92 Å from H15B and the deepest hole 0.14 Å from C15.

Computing details top

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1989); cell refinement: CAD-4 EXPRESS (Enraf–Nonius, 1989); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound. Displacement ellipsoids are drawn at the 20% probability level. Hydrogen bonds are shown as dashed lines. [Symmetry code: (i) -x, 2 - y, -z.]
[Figure 2] Fig. 2. A packing diagram of the title compound, viewed down the a-axis, showing hydrogen bonds (dashed lines) linking the molecules into chains. H atoms not involved in hydrogen bonds have been omitted for clarity.
Diaquabis(4-chlorobenzoato-κO)bis(N,N-diethylnicotinamide-κN1)manganese(II) top
Crystal data top
[Mn(C7H4ClO2)2(C10H14N2O)2(H2O)2]Z = 1
Mr = 758.54F000 = 395
Triclinic, P1Dx = 1.362 Mg m−3
Hall symbol: -P 1Mo Kα radiation
λ = 0.71073 Å
a = 7.3552 (1) ÅCell parameters from 25 reflections
b = 8.6465 (2) Åθ = 5.2–11.6º
c = 15.9847 (3) ŵ = 0.56 mm−1
α = 84.500 (16)ºT = 294 (2) K
β = 78.616 (17)ºBlock, colorless
γ = 68.154 (17)º0.30 × 0.15 × 0.10 mm
V = 924.73 (12) Å3
Data collection top
Enraf–Nonius TurboCAD-4
diffractometer		Rint = 0.062
Radiation source: fine-focus sealed tubeθmax = 26.3º
Monochromator: graphiteθmin = 3.0º
T = 294(2) Kh = −8→9
ω scansk = 0→10
Absorption correction: ψ scan
(North et al., 1968)		l = −19→19
Tmin = 0.902, Tmax = 0.9503 standard reflections
4010 measured reflections every 120 min
3752 independent reflections intensity decay: 1%
2604 reflections with I > 2σ(I)
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)] = 0.080H atoms treated by a mixture of
independent and constrained refinement
wR(F2) = 0.254  w = 1/[σ2(Fo2) + (0.1471P)2 + 1.5562P]
where P = (Fo2 + 2Fc2)/3
S = 1.04(Δ/σ)max < 0.001
3752 reflectionsΔρmax = 1.26 e Å−3
225 parametersΔρmin = −1.31 e Å−3
5 restraintsExtinction correction: none
Primary atom site location: structure-invariant direct methods
Crystal data top
[Mn(C7H4ClO2)2(C10H14N2O)2(H2O)2]γ = 68.154 (17)º
Mr = 758.54V = 924.73 (12) Å3
Triclinic, P1Z = 1
a = 7.3552 (1) ÅMo Kα
b = 8.6465 (2) ŵ = 0.56 mm−1
c = 15.9847 (3) ÅT = 294 (2) K
α = 84.500 (16)º0.30 × 0.15 × 0.10 mm
β = 78.616 (17)º
Data collection top
Enraf–Nonius TurboCAD-4
diffractometer		2604 reflections with I > 2σ(I)
Absorption correction: ψ scan
(North et al., 1968)		Rint = 0.062
Tmin = 0.902, Tmax = 0.9503 standard reflections
4010 measured reflections every 120 min
3752 independent reflections intensity decay: 1%
Refinement top
R[F2 > 2σ(F2)] = 0.0805 restraints
wR(F2) = 0.254H atoms treated by a mixture of
independent and constrained refinement
S = 1.04Δρmax = 1.26 e Å−3
3752 reflectionsΔρmin = −1.31 e Å−3
225 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Mn0.00001.00000.00000.0323 (3)
Cl−0.7397 (3)0.8445 (3)0.46709 (13)0.0925 (7)
O1−0.1119 (5)0.8758 (4)0.1086 (2)0.0408 (8)
O20.0744 (5)0.8690 (5)0.2036 (3)0.0508 (10)
O3−0.8388 (6)1.3270 (5)0.1267 (3)0.0576 (11)
O4−0.2247 (6)0.9829 (5)−0.0681 (2)0.0463 (9)
H41−0.195 (10)1.042 (7)−0.122 (2)0.07 (2)*
H42−0.221 (12)0.880 (5)−0.083 (4)0.08 (2)*
N1−0.2326 (6)1.2447 (5)0.0532 (3)0.0360 (9)
N2−0.8349 (8)1.4183 (8)0.2506 (4)0.0649 (15)
C1−0.0808 (7)0.8688 (6)0.1836 (3)0.0366 (11)
C2−0.2462 (7)0.8636 (5)0.2547 (3)0.0350 (10)
C3−0.4206 (7)0.8580 (6)0.2372 (3)0.0381 (11)
H3−0.43580.85890.18070.046*
C4−0.5733 (8)0.8509 (7)0.3024 (4)0.0487 (13)
H4−0.68980.84630.29040.058*
C5−0.5477 (9)0.8509 (8)0.3850 (4)0.0525 (14)
C6−0.3789 (9)0.8586 (8)0.4047 (4)0.0533 (14)
H6−0.36550.85850.46130.064*
C7−0.2282 (8)0.8665 (7)0.3392 (3)0.0434 (12)
H7−0.11380.87390.35200.052*
C8−0.2050 (7)1.3893 (6)0.0424 (3)0.0390 (11)
H8−0.08551.39170.01070.047*
C9−0.3452 (8)1.5356 (6)0.0760 (4)0.0461 (13)
H9−0.32031.63430.06760.055*
C10−0.5227 (8)1.5332 (6)0.1223 (4)0.0442 (13)
H10−0.61971.63040.14580.053*
C11−0.5554 (7)1.3848 (6)0.1334 (3)0.0359 (11)
C12−0.4080 (7)1.2446 (6)0.0965 (3)0.0380 (11)
H12−0.43151.14530.10200.046*
C13−0.7519 (7)1.3715 (6)0.1710 (3)0.0413 (12)
C14−0.7427 (13)1.4762 (10)0.3087 (5)0.080 (2)
H14A−0.62471.49350.27700.096*
H14B−0.83501.58230.33180.096*
C15−0.6883 (17)1.3572 (14)0.3785 (7)0.132
H15A−0.62901.39890.41510.132*
H15B−0.59491.25270.35580.132*
H15C−0.80521.34120.41060.132*
C16−1.0402 (11)1.4197 (10)0.2815 (6)0.080 (2)
H16A−1.10311.49420.32910.096*
H16B−1.11771.46160.23620.096*
C17−1.0391 (16)1.2541 (11)0.3085 (7)0.107 (3)
H17A−1.17341.25890.32720.160*
H17B−0.96591.21370.35460.160*
H17C−0.97731.18020.26140.160*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Mn0.0261 (5)0.0275 (5)0.0373 (6)−0.0030 (4)−0.0004 (4)−0.0107 (4)
Cl0.0696 (12)0.144 (2)0.0638 (12)−0.0517 (13)0.0190 (9)−0.0096 (12)
O10.043 (2)0.0384 (19)0.0390 (19)−0.0133 (16)−0.0033 (15)−0.0072 (14)
O20.034 (2)0.061 (3)0.057 (2)−0.0162 (18)−0.0097 (17)−0.0010 (19)
O30.043 (2)0.066 (3)0.070 (3)−0.022 (2)−0.0078 (19)−0.022 (2)
O40.043 (2)0.046 (2)0.054 (2)−0.0195 (17)−0.0090 (17)−0.0081 (18)
N10.030 (2)0.026 (2)0.046 (2)−0.0054 (16)−0.0002 (17)−0.0086 (16)
N20.052 (3)0.079 (4)0.061 (3)−0.026 (3)0.011 (2)−0.024 (3)
C10.031 (2)0.022 (2)0.049 (3)−0.0010 (18)−0.007 (2)−0.0055 (19)
C20.034 (2)0.022 (2)0.044 (3)−0.0032 (18)−0.006 (2)−0.0050 (18)
C30.037 (3)0.033 (3)0.043 (3)−0.012 (2)−0.007 (2)−0.005 (2)
C40.036 (3)0.058 (3)0.055 (3)−0.021 (3)−0.005 (2)−0.005 (3)
C50.044 (3)0.055 (3)0.051 (3)−0.015 (3)0.005 (3)−0.005 (3)
C60.055 (3)0.064 (4)0.038 (3)−0.018 (3)−0.006 (2)−0.001 (3)
C70.036 (3)0.045 (3)0.047 (3)−0.010 (2)−0.008 (2)−0.008 (2)
C80.032 (2)0.032 (2)0.051 (3)−0.009 (2)−0.005 (2)−0.009 (2)
C90.042 (3)0.030 (3)0.066 (4)−0.012 (2)−0.007 (3)−0.009 (2)
C100.040 (3)0.027 (2)0.059 (3)−0.003 (2)−0.005 (2)−0.018 (2)
C110.031 (2)0.032 (2)0.040 (3)−0.0040 (19)−0.0066 (19)−0.0103 (19)
C120.030 (2)0.028 (2)0.050 (3)−0.0054 (19)0.000 (2)−0.010 (2)
C130.031 (2)0.038 (3)0.051 (3)−0.007 (2)−0.003 (2)−0.013 (2)
C140.085 (5)0.078 (5)0.072 (5)−0.029 (4)−0.002 (4)−0.009 (4)
C150.1800.1560.138−0.130−0.1270.126
C160.060 (4)0.067 (5)0.098 (6)−0.015 (4)0.018 (4)−0.026 (4)
C170.116 (8)0.071 (6)0.112 (7)−0.031 (5)0.030 (6)−0.014 (5)
Geometric parameters (Å, °) top
Mn—O1i2.141 (3)C7—C61.383 (8)
Mn—O12.141 (3)C7—H70.9300
Mn—O42.205 (4)C8—H80.9300
Mn—O4i2.205 (4)C9—C81.376 (7)
Mn—N1i2.281 (4)C9—H90.9300
Mn—N12.281 (4)C10—C91.373 (8)
Cl—C51.741 (6)C10—H100.9300
O1—C11.256 (6)C11—C121.378 (6)
O2—C11.245 (6)C11—C101.380 (7)
O3—C131.214 (6)C12—H120.9300
O4—H410.99 (4)C13—N21.328 (7)
O4—H420.93 (5)C13—C111.494 (7)
N1—C81.330 (6)C14—C151.453 (9)
N1—C121.339 (6)C14—H14A0.9700
N2—C141.471 (10)C14—H14B0.9700
N2—C161.489 (9)C15—H15A0.9600
C2—C31.384 (7)C15—H15B0.9600
C2—C71.387 (7)C15—H15C0.9600
C2—C11.502 (7)C16—C171.453 (11)
C3—H30.9300C16—H16A0.9700
C4—C51.369 (8)C16—H16B0.9700
C4—C31.388 (7)C17—H17A0.9600
C4—H40.9300C17—H17B0.9600
C5—C61.366 (9)C17—H17C0.9600
C6—H60.9300
O1i—Mn—O1180.000 (1)C6—C7—H7119.7
O1i—Mn—O490.38 (14)C2—C7—H7119.7
O1—Mn—O489.62 (14)N1—C8—C9122.9 (5)
O1i—Mn—O4i89.62 (14)N1—C8—H8118.5
O1—Mn—O4i90.38 (14)C9—C8—H8118.5
O4—Mn—O4i180.00 (16)C10—C9—C8118.8 (5)
O1i—Mn—N1i87.77 (14)C10—C9—H9120.6
O1—Mn—N1i92.23 (14)C8—C9—H9120.6
O4—Mn—N1i92.72 (14)C9—C10—C11119.2 (4)
O4i—Mn—N1i87.28 (14)C9—C10—H10120.4
O1i—Mn—N192.23 (14)C11—C10—H10120.4
O1—Mn—N187.77 (14)C12—C11—C10118.2 (5)
O4—Mn—N187.28 (14)C12—C11—C13117.2 (4)
O4i—Mn—N192.72 (14)C10—C11—C13123.8 (4)
N1i—Mn—N1180.0N1—C12—C11123.0 (5)
C1—O1—Mn127.5 (3)N1—C12—H12118.5
Mn—O4—H41100 (4)C11—C12—H12118.5
Mn—O4—H42121 (5)O3—C13—N2120.8 (5)
H41—O4—H42107 (4)O3—C13—C11119.4 (5)
C8—N1—C12117.7 (4)N2—C13—C11119.7 (5)
C8—N1—Mn123.5 (3)C15—C14—N2111.7 (7)
C12—N1—Mn118.8 (3)C15—C14—H14A109.3
C13—N2—C14124.8 (6)N2—C14—H14A109.3
C13—N2—C16117.3 (6)C15—C14—H14B109.3
C14—N2—C16117.8 (6)N2—C14—H14B109.3
O2—C1—O1125.2 (5)H14A—C14—H14B107.9
O2—C1—C2117.6 (5)C14—C15—H15A109.5
O1—C1—C2117.1 (4)C14—C15—H15B109.5
C3—C2—C7118.6 (5)H15A—C15—H15B109.5
C3—C2—C1120.8 (5)C14—C15—H15C109.5
C7—C2—C1120.6 (5)H15A—C15—H15C109.5
C2—C3—C4121.2 (5)H15B—C15—H15C109.5
C2—C3—H3119.4C17—C16—N2111.5 (7)
C4—C3—H3119.4C17—C16—H16A109.3
C5—C4—C3118.2 (5)N2—C16—H16A109.3
C5—C4—H4120.9C17—C16—H16B109.3
C3—C4—H4120.9N2—C16—H16B109.3
C6—C5—C4122.2 (5)H16A—C16—H16B108.0
C6—C5—Cl119.3 (5)C16—C17—H17A109.5
C4—C5—Cl118.5 (5)C16—C17—H17B109.5
C5—C6—C7119.1 (5)H17A—C17—H17B109.5
C5—C6—H6120.5C16—C17—H17C109.5
C7—C6—H6120.5H17A—C17—H17C109.5
C6—C7—C2120.6 (5)H17B—C17—H17C109.5
O4—Mn—O1—C1−164.0 (4)C7—C2—C1—O22.8 (7)
O4i—Mn—O1—C116.0 (4)C3—C2—C1—O13.3 (6)
N1i—Mn—O1—C1103.3 (4)C7—C2—C1—O1−175.9 (4)
N1—Mn—O1—C1−76.7 (4)C7—C2—C3—C4−1.7 (7)
O1i—Mn—N1—C8−32.0 (4)C1—C2—C3—C4179.1 (5)
O1—Mn—N1—C8148.0 (4)C5—C4—C3—C20.5 (8)
O4—Mn—N1—C8−122.3 (4)C3—C4—C5—C60.4 (9)
O4i—Mn—N1—C857.7 (4)C3—C4—C5—Cl179.2 (4)
O1i—Mn—N1—C12146.8 (4)C4—C5—C6—C7−0.1 (10)
O1—Mn—N1—C12−33.2 (4)Cl—C5—C6—C7−178.9 (5)
O4—Mn—N1—C1256.6 (4)C2—C7—C6—C5−1.2 (9)
O4i—Mn—N1—C12−123.4 (4)C10—C9—C8—N1−0.6 (9)
Mn—O1—C1—O2−31.6 (7)C11—C10—C9—C8−0.2 (8)
Mn—O1—C1—C2146.9 (3)C12—C11—C10—C9−0.7 (8)
Mn—N1—C8—C9−178.9 (4)C13—C11—C10—C9−170.7 (5)
C12—N1—C8—C92.2 (8)C10—C11—C12—N12.4 (8)
C8—N1—C12—C11−3.2 (8)C13—C11—C12—N1173.1 (5)
Mn—N1—C12—C11177.9 (4)O3—C13—N2—C14−179.1 (6)
C13—N2—C14—C15−111.0 (9)C11—C13—N2—C14−3.4 (10)
C16—N2—C14—C1572.0 (10)O3—C13—N2—C16−2.2 (9)
C13—N2—C16—C1781.2 (9)C11—C13—N2—C16173.5 (5)
C14—N2—C16—C17−101.6 (9)O3—C13—C11—C10114.1 (6)
C3—C2—C7—C62.0 (8)N2—C13—C11—C10−61.6 (8)
C1—C2—C7—C6−178.8 (5)O3—C13—C11—C12−55.9 (7)
C3—C2—C1—O2−178.0 (4)N2—C13—C11—C12128.3 (6)
Symmetry codes: (i) −x, −y+2, −z.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O4—H41···O2i0.99 (4)1.71 (5)2.670 (6)162 (7)
O4—H42···O3ii0.93 (5)1.85 (5)2.766 (6)168 (7)
Symmetry codes: (i) −x, −y+2, −z; (ii) −x−1, −y+2, −z.
Table 1
Selected geometric parameters (Å, °) top
Mn—O12.141 (3)Mn—N12.281 (4)
Mn—O42.205 (4)
O1i—Mn—O490.38 (14)O4—Mn—N1i92.72 (14)
O1—Mn—O489.62 (14)O1—Mn—N187.77 (14)
O1—Mn—N1i92.23 (14)O4—Mn—N187.28 (14)
Symmetry codes: (i) −x, −y+2, −z.
Table 2
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O4—H41···O2i0.99 (4)1.71 (5)2.670 (6)162 (7)
O4—H42···O3ii0.93 (5)1.85 (5)2.766 (6)168 (7)
Symmetry codes: (i) −x, −y+2, −z; (ii) −x−1, −y+2, −z.
Acknowledgements top

The authors acknowledge the purchase of a CAD-4 diffractometer under grant DPT/TBAG1 of the Scientific and Technical Research Council of Turkey.

references
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