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Acta Cryst. (2012). E68, m1568-m1569    [ doi:10.1107/S160053681204826X ]

Diammine{N-[2-(hydroxyimino)propionyl]-N'-[2-(oxidoimino)propionyl]propane-1,3-diaminido-[kappa]4N,N',N'',N'''}iron(III)

S. Tomyn, M. Haukka and R. Nedelkov

Abstract top

In the title compound, [Fe(C9H13N4O4)(NH3)2], the FeIII atom, lying on a mirror plane, is coordinated by four N atoms of a triply deprotonated tetradentate N-[2-(hydroxyimino)propionyl]-N'-[2-(oxidoimino)propionyl]propane-1,3-diaminide ligand in the equatorial plane and two N atoms of two ammonia molecules at the axial positions in a distorted octahedral geometry. A short intramolecular O-H...O hydrogen bond between the cis-disposed oxime O atoms stabilizes the pseudo-macrocyclic configuration of the ligand. In the crystal, molecules are linked by N-H...O hydrogen bonds into a three-dimensional network. The ligand has a mirror-plane symmetry. One of the methylene groups of the propane bridge is disordered over two sets of sites with equal occupancy factors.

Comment top

Polydentate oxime ligands containing both oxime and other donor functions (e.g. carboxylic, amide, hydroxamic) draw considerable attention during past two decades due to their potential for the bridging mode of coordination and mediation of strong magnetic exchange interactions between metal ions (Moroz et al., 2008, 2010; Skopenko et al., 1990) and for the preparation of metal complexes with efficient stabilization of unusually high oxidation states of 3d-metal ions (Fritsky et al., 1998, 2006; Kanderal et al., 2005). The open-chain tetradentate oxime-and-amide ligands were the subjects of several studies carried out in our group, and a series of mono- and polynuclear complexes of copper(III), nickel(II) and cobalt(III) have been reported within past 15 years (Duda et al., 1997; Fritsky et al., 2004, 2006; Kanderal et al., 2005; Kufelnicki et al., 2010). As a part of our research study of open-chain tetradentate oxime-and-amide ligands, we present the structure of the title compound containing iron(III) as a central atom.

In the title compound, FeIII ion, lying on a mirror plane, is coordinated by four N atoms of a triply deprotonated tetradentate ligand, N,N'-bis(2-hydroxyiminopropionyl)propane-1,3-diamine, in the equatorial plane and by two N atoms of two ammonia molecules at the axial postions in a distorted octahedral geometry (Fig. 1). The tetradentate ligand coordinates the FeIII atom in a planar fashion, forming three condensed 5-, 6- and 5-membered chelate rings. All angles around the FeIII atom deviate insignificantly from 90°. There are no alternating deviations for N(oxime) and N(amide) atoms from the N1, N2, N3 and N4 plane. The values of Fe—N(amide) and Fe—N(oxime) bond lengths in the equatorial plane are in the range of 1.909 (2)–1.917 (2) Å. The distance between the FeIII atom and the two axial N atom is 1.993 (3) Å. Bond lengths of N—C and C═O of the amide groups are 1.323 (3)–1.327 (3) and 1.252 (3)–1.255 (3) Å, respectively, and are typical for the deprotonated amide groups (Dvorkin et al., 1990a, b; Lampeka et al., 1989; Onindo et al., 1995). The bond lengths N—O and C═N of the oxime groups are 1.349 (3)–1.364 (3) and 1.291 (3)–1.292 (3) Å, respectively, that is typical for the amide derivatives of 2-hydroxypropanoic acid (Duda et al., 1997; Mokhir et al., 2002; Onindo et al., 1995; Sliva et al., 1997a, b). In the crystal, the complex molecules are linked by intermolecular N—H···O hydrogen bonds formed between the coordinated ammonia molecules and O atoms of the ligand into a three-dimensional network (Fig. 2). An intramolecular O—H···O hydrogen bond is also present. One of the methylene groups of the propane bridge is disordered in a 0.5:0.5 ratio.

Related literature top

For oximes as potential bridging ligands, see: Moroz et al. (2008, 2010); Skopenko et al. (1990). For oximes stabilizing high oxidation states of metal ions, see: Fritsky et al. (1998, 2006); Kanderal et al. (2005). For coordination chemistry of tetradentate oxime-and-amide open-chain ligands, see: Duda et al. (1997); Fritsky et al. (2004); Kufelnicki et al. (2010). For related structures, see: Dvorkin et al. (1990a,b); Lampeka et al. (1989); Mokhir et al. (2002); Onindo et al. (1995); Sliva et al. (1997a,b).

Experimental top

Fe(ClO4).6H2O (0.363 g, 1 mmol) was dissolved in 5 ml of DMSO and added to a solution of N,N'-bis(2-hydroxyiminopropionyl)propane-1,3-diamine (0.246 g, 1 mmol) in 10 ml of DMSO. The resulting deep orange mixture was stirred for 15 min at room temperature, filtered off and set aside for crystallization at ambient conditions in an ammonia atmosphere. Red insoluble crystals of the title compound suitable for X-ray analysis were obtained in 24 h (yield: 0.227 g, 68%). Analysis, calculated for C9H19FeN6O4: C 39.27, H 6.96, N 30.53%; found: C 39.59, H 7.02, N 30.84%.

Refinement top

C5 atom and all C-bound H atoms were disordered over two sets of sites across the mirror plane, with equal occupancies. These H atoms were positioned geometrically and refined as riding atoms, with C—H = 0.99 (CH2) and 0.98 (CH3) Å and Uiso(H) = 1.2(1.5 for methyl)Ueq(C). H atoms of OH and NH3 groups were located from a difference Fourier map and constrained to ride on their parent atoms, with Uiso(H) = 1.5Ueq(parent atom).

Computing details top

Data collection: COLLECT (Nonius, 2000); cell refinement: DENZO/SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO/SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level. C5 atom and all C-bound H atoms are disordered over two sets of sites across the mirror plane with equal occupancies. [Symmetry code: (i) x, 3/2-y, z.]
[Figure 2] Fig. 2. A packing diagram of the title compound. Hydrogen bonds are indicated by dashed lines. H atoms not involved in hydrogen bonds have been omitted for clarity.
Diammine{N-[2-(hydroxyimino)propionyl]-N'-[2- (oxidoimino)propionyl]propane-1,3-diaminido- κ4N,N',N'',N'''}iron(III) top
Crystal data top
[Fe(C9H13N4O4)(NH3)2]F(000) = 346.0
Mr = 331.15Dx = 1.701 Mg m−3
Monoclinic, P21/mMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybCell parameters from 2700 reflections
a = 8.9111 (3) Åθ = 1.0–27.5°
b = 7.2255 (3) ŵ = 1.19 mm−1
c = 10.6194 (4) ÅT = 100 K
β = 108.994 (2)°Block, red
V = 646.52 (4) Å30.20 × 0.09 × 0.04 mm
Z = 2
Data collection top
Nonius KappaCCD
diffractometer		1599 independent reflections
Radiation source: fine-focus sealed tube1361 reflections with I > 2σ(I)
Horizontally mounted graphite crystal monochromatorRint = 0.047
Detector resolution: 9 pixels mm-1θmax = 27.5°, θmin = 2.4°
φ and ω scans with κ offseth = −11→11
Absorption correction: multi-scan
(DENZO/SCALEPACK; Otwinowski & Minor, 1997)		k = −9→9
Tmin = 0.795, Tmax = 0.954l = −13→13
12359 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.030Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.074H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.028P)2 + 0.7141P]
where P = (Fo2 + 2Fc2)/3
1599 reflections(Δ/σ)max < 0.001
124 parametersΔρmax = 0.58 e Å−3
0 restraintsΔρmin = −0.46 e Å−3
Crystal data top
[Fe(C9H13N4O4)(NH3)2]V = 646.52 (4) Å3
Mr = 331.15Z = 2
Monoclinic, P21/mMo Kα radiation
a = 8.9111 (3) ŵ = 1.19 mm−1
b = 7.2255 (3) ÅT = 100 K
c = 10.6194 (4) Å0.20 × 0.09 × 0.04 mm
β = 108.994 (2)°
Data collection top
Nonius KappaCCD
diffractometer		1599 independent reflections
Absorption correction: multi-scan
(DENZO/SCALEPACK; Otwinowski & Minor, 1997)		1361 reflections with I > 2σ(I)
Tmin = 0.795, Tmax = 0.954Rint = 0.047
12359 measured reflectionsθmax = 27.5°
Refinement top
R[F2 > 2σ(F2)] = 0.030H-atom parameters constrained
wR(F2) = 0.074Δρmax = 0.58 e Å−3
S = 1.04Δρmin = −0.46 e Å−3
1599 reflectionsAbsolute structure: ?
124 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
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)
Fe10.84000 (4)0.75000.68148 (4)0.01316 (12)
O11.1762 (2)0.75000.72129 (19)0.0199 (4)
H1O1.11800.75000.62580.030*
O20.9831 (2)0.75001.07989 (18)0.0220 (4)
O30.4412 (2)0.75000.36943 (19)0.0196 (4)
O40.9952 (2)0.75000.48443 (18)0.0162 (4)
N50.85135 (18)1.0255 (2)0.67972 (15)0.0151 (3)
H5D0.90631.06180.62520.023*
H5E0.90161.06740.76370.023*
H5F0.75141.07300.64940.023*
N11.0616 (3)0.75000.7808 (2)0.0148 (4)
N20.8273 (3)0.75000.8580 (2)0.0149 (4)
N30.6183 (3)0.75000.5839 (2)0.0146 (4)
N40.8536 (2)0.75000.5050 (2)0.0135 (4)
C11.1043 (3)0.75000.9092 (3)0.0166 (5)
C21.2708 (3)0.75000.9983 (3)0.0243 (6)
H2A1.27410.72151.08940.036*0.50
H2B1.31770.87220.99640.036*0.50
H2C1.33100.65630.96810.036*0.50
C30.9631 (3)0.75000.9576 (3)0.0162 (5)
C40.6775 (3)0.75000.8870 (3)0.0191 (6)
H4A0.69400.81190.97360.023*0.50
H4B0.64560.62050.89520.023*0.50
C50.5460 (4)0.8461 (6)0.7819 (4)0.0181 (8)0.50
H5A0.58110.97330.77080.022*0.50
H5B0.45340.85640.81360.022*0.50
C60.4926 (3)0.75000.6449 (3)0.0187 (6)
H6A0.46180.62070.65550.022*0.50
H6B0.39810.81450.58520.022*0.50
C70.5789 (3)0.75000.4522 (3)0.0152 (5)
C80.7221 (3)0.75000.4066 (3)0.0152 (5)
C90.7113 (3)0.75000.2641 (3)0.0229 (6)
H9A0.73490.87420.23860.034*0.50
H9B0.60380.71420.20920.034*0.50
H9C0.78800.66160.25050.034*0.50
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Fe10.01225 (19)0.0146 (2)0.01244 (19)0.0000.00372 (14)0.000
O10.0132 (9)0.0290 (11)0.0181 (10)0.0000.0062 (8)0.000
O20.0250 (10)0.0279 (11)0.0107 (9)0.0000.0027 (8)0.000
O30.0121 (9)0.0254 (11)0.0183 (10)0.0000.0006 (7)0.000
O40.0119 (8)0.0212 (10)0.0174 (9)0.0000.0073 (7)0.000
N50.0155 (7)0.0153 (8)0.0139 (7)0.0005 (6)0.0041 (6)0.0013 (6)
N10.0135 (10)0.0150 (11)0.0162 (11)0.0000.0052 (8)0.000
N20.0150 (10)0.0172 (11)0.0131 (10)0.0000.0052 (8)0.000
N30.0128 (10)0.0175 (11)0.0142 (11)0.0000.0053 (8)0.000
N40.0120 (10)0.0139 (11)0.0153 (11)0.0000.0053 (8)0.000
C10.0172 (13)0.0147 (13)0.0147 (12)0.0000.0007 (10)0.000
C20.0201 (14)0.0317 (17)0.0174 (14)0.0000.0011 (11)0.000
C30.0201 (13)0.0128 (12)0.0134 (12)0.0000.0025 (10)0.000
C40.0181 (13)0.0229 (14)0.0181 (13)0.0000.0086 (11)0.000
C50.0158 (17)0.020 (2)0.0206 (19)0.0000 (15)0.0091 (15)0.0001 (15)
C60.0135 (12)0.0250 (15)0.0187 (13)0.0000.0067 (10)0.000
C70.0147 (12)0.0127 (12)0.0174 (12)0.0000.0042 (10)0.000
C80.0153 (12)0.0157 (12)0.0146 (12)0.0000.0048 (10)0.000
C90.0190 (14)0.0350 (17)0.0124 (13)0.0000.0022 (11)0.000
Geometric parameters (Å, º) top
Fe1—N31.909 (2)N4—O4i1.349 (3)
Fe1—N11.912 (2)C1—C21.478 (4)
Fe1—N21.914 (2)C1—C31.506 (4)
Fe1—N41.917 (2)C2—H2A0.9800
Fe1—N51.9932 (16)C2—H2B0.9800
O1—N11.364 (3)C2—H2C0.9800
O1—H1O0.9769C4—C51.500 (4)
O2—C31.252 (3)C4—H4A0.9900
O3—C71.255 (3)C4—H4B0.9900
O4—O4i0.000 (4)C5—C61.541 (4)
O4—N41.349 (3)C5—H5A0.9900
N5—H5D0.9100C5—H5B0.9900
N5—H5E0.9100C6—H6A0.9900
N5—H5F0.9100C6—H6B0.9900
N1—C11.291 (3)C7—C81.505 (4)
N2—C31.323 (3)C8—C91.485 (4)
N2—C41.464 (3)C9—H9A0.9800
N3—C71.327 (3)C9—H9B0.9800
N3—C61.465 (3)C9—H9C0.9800
N4—C81.292 (3)
N3—Fe1—N1179.44 (10)C1—C2—H2A109.5
N3—Fe1—N298.66 (9)C1—C2—H2B109.5
N1—Fe1—N280.78 (9)H2A—C2—H2B109.5
N3—Fe1—N481.55 (9)C1—C2—H2C109.5
N1—Fe1—N499.01 (9)H2A—C2—H2C109.5
N2—Fe1—N4179.79 (9)H2B—C2—H2C109.5
N3—Fe1—N592.39 (4)O2—C3—N2127.8 (3)
N1—Fe1—N587.63 (5)O2—C3—C1120.1 (2)
N2—Fe1—N591.64 (5)N2—C3—C1112.0 (2)
N4—Fe1—N588.35 (5)N2—C4—C5112.9 (2)
N3—Fe1—N5i92.39 (5)N2—C4—H4A109.0
N1—Fe1—N5i87.63 (4)C5—C4—H4A109.0
N2—Fe1—N5i91.64 (5)N2—C4—H4B109.0
N4—Fe1—N5i88.35 (5)C5—C4—H4B109.0
N5—Fe1—N5i173.75 (9)H4A—C4—H4B107.8
N1—O1—H1O104.8C4—C5—C6114.8 (3)
Fe1—N5—H5D109.5C4—C5—H5A108.6
Fe1—N5—H5E109.5C6—C5—H5A108.6
H5D—N5—H5E109.5C4—C5—H5B108.6
Fe1—N5—H5F109.5C6—C5—H5B108.6
H5D—N5—H5F109.5H5A—C5—H5B107.5
H5E—N5—H5F109.5N3—C6—C5111.8 (2)
C1—N1—O1118.8 (2)N3—C6—H6A109.3
C1—N1—Fe1118.60 (18)C5—C6—H6A109.3
O1—N1—Fe1122.60 (16)N3—C6—H6B109.3
C3—N2—C4119.4 (2)C5—C6—H6B109.3
C3—N2—Fe1116.91 (18)H6A—C6—H6B107.9
C4—N2—Fe1123.68 (17)O3—C7—N3127.0 (2)
C7—N3—C6119.2 (2)O3—C7—C8120.8 (2)
C7—N3—Fe1116.37 (17)N3—C7—C8112.2 (2)
C6—N3—Fe1124.43 (17)N4—C8—C9124.4 (2)
C8—N4—O4i121.3 (2)N4—C8—C7112.4 (2)
C8—N4—O4121.3 (2)C9—C8—C7123.2 (2)
C8—N4—Fe1117.49 (18)C8—C9—H9A109.5
O4i—N4—Fe1121.24 (16)C8—C9—H9B109.5
O4—N4—Fe1121.24 (16)H9A—C9—H9B109.5
N1—C1—C2124.4 (3)C8—C9—H9C109.5
N1—C1—C3111.7 (2)H9A—C9—H9C109.5
C2—C1—C3123.9 (2)H9B—C9—H9C109.5
N5—Fe1—N1—C192.04 (4)N5—Fe1—N4—C8−92.66 (4)
N5i—Fe1—N1—C1−92.04 (4)N5i—Fe1—N4—C892.66 (4)
N5—Fe1—N1—O1−87.96 (4)N5—Fe1—N4—O4i87.34 (4)
N5i—Fe1—N1—O187.96 (4)N5i—Fe1—N4—O4i−87.34 (4)
N5—Fe1—N2—C3−87.34 (4)N5—Fe1—N4—O487.34 (4)
N5i—Fe1—N2—C387.34 (4)N5i—Fe1—N4—O4−87.34 (4)
N5—Fe1—N2—C492.66 (4)C3—N2—C4—C5149.83 (18)
N5i—Fe1—N2—C4−92.66 (4)Fe1—N2—C4—C5−30.17 (18)
N5—Fe1—N3—C787.98 (5)N2—C4—C5—C666.1 (3)
N5i—Fe1—N3—C7−87.98 (5)C7—N3—C6—C5−150.96 (17)
N5—Fe1—N3—C6−92.02 (5)Fe1—N3—C6—C529.04 (17)
N5i—Fe1—N3—C692.02 (5)C4—C5—C6—N3−65.3 (3)
Symmetry code: (i) x, −y+3/2, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1O···O40.981.542.508 (3)168
N5—H5D···O4ii0.912.153.015 (2)158
N5—H5E···O2iii0.912.112.979 (2)160
N5—H5F···O3iv0.912.102.969 (2)160
Symmetry codes: (ii) −x+2, y+1/2, −z+1; (iii) −x+2, y+1/2, −z+2; (iv) −x+1, y+1/2, −z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1O···O40.981.542.508 (3)168
N5—H5D···O4i0.912.153.015 (2)158
N5—H5E···O2ii0.912.112.979 (2)160
N5—H5F···O3iii0.912.102.969 (2)160
Symmetry codes: (i) −x+2, y+1/2, −z+1; (ii) −x+2, y+1/2, −z+2; (iii) −x+1, y+1/2, −z+1.
Acknowledgements top

Financial support from the State Fund for Fundamental Researches of Ukraine (grant No. F40.3/041) is gratefully acknowledged.

references
References top

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