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Acta Cryst. (2009). E65, o2077-o2078    [ doi:10.1107/S1600536809029778 ]

N-(2-Hydroxyethyl)-2-[2-(hydroxyimino)propanamido]ethanaminium 2-(hydroxyimino)propanoate

T. S. Iskenderov, V. A. Kalibabchuk, I. A. Golenya, N. M. Dudarenko and N. I. Usenko

Abstract top

The cation of the title salt, C7H16N3O3+·C3H4NO3-, the oxime group is trans with respect to the amide-carbonyl group. The components of the structure are united into a three-dimensional network by an extensive system of O-H...O and N-H...O hydrogen bonds.

Comment top

Oximes are classical type of chelating ligands traditionally widely used in coordination and analytical chemistry (Kukushkin et al., 1996; Chaudhuri, 2003). They are also important bridging ligands extensively used in molecular magnetism for obtaining of polynuclear complexes (Cervera et al., 1997; Costes et al., 1998; Moroz et al., 2008). The presence of an additional donor function in the vicinity to the oxime group may result in important increase of chelating efficiency and ability to form polynuclear species. For example, amide derivatives of 2-hydroxyiminopropanoic acid were shown to act as highly efficient chelators with respect to Cu(II), Ni(II) and Al(III) (Onindo et al., 1995; Sliva et al., 1997a; Sliva, et al., 1997b; Gumienna-Kontecka et al., 2000). Recently, owing to their strong σ-donor capacity, open-chain tetradentate oxime and amide ligands were shown to efficiently stabilize unusual oxidation states of metal ions, such as Cu3+ and Ni3+ (Kanderal et al., 2005; Fritsky et al., 2006). The present investigation is dedicated to the study of the molecular structure of the title compound (I), which is a new polynucleative ligand containing several donor functions: oxime, amine, amide and alcohol.

The structure of (I) is ionic and and comprises cations of N-[2-(2-hydroxy-ethylammonium)ethyl]-2-hydroxyiminopropanamide and 2-(hydroxyimino)propanoate anions (Fig. 1). The cation has a Γ-shaped conformation and consists of two nearly planar CH3C(=NOH)C(O)NHCH2 and CH2CH2NH2CH2 fragments. The dihedral plane between their mean planes, defined by the non-hydrogen atoms, is 75.8 (1)°. The hydroxyl group is situated nearly perpendicular to the CH2CH2NH2CH2 moiety: the torsion angle N4/C9/C10/O6 is 60.2 (2)°. The observed conformation of the CH3C(=NOH)C(O)NHCH2 moiety is the same as that observed in the structure of N,N'-bis(2-hydroxyiminopropionylpropane)-1,2-diamine and its homologues (Duda et al., 1997; Fritsky, Karaczyn et al., 1999). The oxime group is trans to the amide-carbonyl. It is noted that the CH3C(=NOH)C(O)NHCH2 moiety deviates somewhat from planarity because of a twisting of the oxime and amide groups along the C5—C6 bond. The dihedral angle between the corresponding least square planes is 9.5 (1)°. The C=N, C=O, N—O, C—N bond lengths are typical for 2-hydroxyiminopropanoic acid and its amide derivatives (Duda et al., 1997; Fritsky, 1999; Mokhir et al., 2002).

The elements of the structure are united into a 3-D network by extensive system of the O—H···O and N—H···O hydrogen bonds (Table 1).

Related literature top

For background to oximes in coordination chemistry, see: Kukushkin et al. (1996); Chaudhuri (2003). For polynuclear species arising from bridging and/or functionalized oximes, see: Cervera et al. (1997); Costes et al. (1998); Moroz et al. (2008); Onindo et al. (1995); Sliva et al. (1997a,b); Gumienna-Kontecka et al. (2000). For oximes stabilizing high oxidation states, see: Kanderal et al. (2005); Fritsky et al. (2006). For related structures, see: Duda et al. (1997); Fritsky et al. (1999); Fritsky (1999); Mokhir et al. (2002). For the synthesis, see: Lau & Gutsche (1978).

Experimental top

Ethyl 2-(hydroxyimino)propanoate (1.31 g, 0.01 mol) was dissolved in methanol (50 ml) to which 2-((2-aminoethyl)amino)ethanol (1.04 g, 0.01 mol) was added. The mixture was set aside for 24 h at room temperature, then the solvent was removed on a rotary evaporator. Recrystallization of the crude product from water afforded the pure (I) in the form of single crystals. Ethyl 2-(hydroxyimino)propanoate was prepared according to the reported method (Lau & Gutsche, 1978).

Refinement top

The O—H and N—H hydrogen atoms were located from the difference Fourier map, and refined with Uiso = 1.5 Ueq(parent atom). The remaining H atoms were positioned geometrically and were constrained to ride on their parent atoms with C—H = 0.96–0.97 Å, and with Uiso = 1.2–1.5 Ueq(parent atom).

Computing details top

Data collection: COLLECT (Bruker, 2004); cell refinement: DENZO/SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO/SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR2004 (Burla et al., 2005); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. A view of compound (I), with displacement ellipsoids shown at the 50% probability level. H atoms are drawn as spheres of arbitrary radii. Hydrogen bonds are indicated by dashed lines.
N-(2-Hydroxyethyl)-2-[2-(hydroxyimino)propanamido]ethanaminium 2-(hydroxyimino)propanoate top
Crystal data top
C7H16N3O3+·C3H4NO3−F(000) = 624
Mr = 292.30Dx = 1.450 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1078 reflections
a = 9.355 (2) Åθ = 3.2–27.5°
b = 6.996 (1) ŵ = 0.12 mm−1
c = 20.606 (4) ÅT = 120 K
β = 96.99 (3)°Block, colourless
V = 1338.6 (4) Å30.30 × 0.24 × 0.20 mm
Z = 4
Data collection top
Nonius KappaCCD
diffractometer		3090 independent reflections
Radiation source: fine-focus sealed tube1887 reflections with I > 2σ(I)
horizontally mounted graphite crystalRint = 0.049
Detector resolution: 9 pixels mm-1θmax = 28.4°, θmin = 3.1°
φ scans and ω scans with κ offseth = −12→9
Absorption correction: multi-scan
(North et al., 1968)		k = −8→9
Tmin = 0.957, Tmax = 0.979l = −23→26
8410 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)] = 0.044Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.088H atoms treated by a mixture of independent and constrained refinement
S = 0.92 w = 1/[σ2(Fo2) + (0.0375P)2]
where P = (Fo2 + 2Fc2)/3
3090 reflections(Δ/σ)max = 0.002
201 parametersΔρmax = 0.20 e Å−3
0 restraintsΔρmin = −0.25 e Å−3
Crystal data top
C7H16N3O3+·C3H4NO3−V = 1338.6 (4) Å3
Mr = 292.30Z = 4
Monoclinic, P21/cMo Kα radiation
a = 9.355 (2) ŵ = 0.12 mm−1
b = 6.996 (1) ÅT = 120 K
c = 20.606 (4) Å0.30 × 0.24 × 0.20 mm
β = 96.99 (3)°
Data collection top
Nonius KappaCCD
diffractometer		3090 independent reflections
Absorption correction: multi-scan
(North et al., 1968)		1887 reflections with I > 2σ(I)
Tmin = 0.957, Tmax = 0.979Rint = 0.049
8410 measured reflectionsθmax = 28.4°
Refinement top
R[F2 > 2σ(F2)] = 0.044H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.088Δρmax = 0.20 e Å−3
S = 0.92Δρmin = −0.25 e Å−3
3090 reflectionsAbsolute structure: ?
201 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*/Ueq
O1−0.84446 (13)−0.16641 (17)0.98706 (6)0.0158 (3)
O2−0.60613 (13)−0.22237 (19)1.00166 (6)0.0180 (3)
O3−0.84727 (14)−0.3817 (2)0.80265 (6)0.0181 (3)
H3O−0.939 (2)−0.373 (3)0.7840 (10)0.027*
O40.55821 (13)0.0801 (2)0.88257 (6)0.0193 (3)
H4O0.583 (2)0.126 (3)0.9258 (10)0.029*
O50.12037 (13)0.11505 (19)0.75400 (6)0.0179 (3)
O6−0.27505 (15)−0.2615 (2)1.00518 (6)0.0211 (3)
H6O−0.369 (2)−0.261 (3)0.9960 (9)0.032*
N1−0.85445 (16)−0.3060 (2)0.86557 (7)0.0146 (4)
N20.41206 (16)0.1204 (2)0.87427 (7)0.0153 (4)
N30.13295 (17)0.1750 (2)0.86292 (8)0.0139 (4)
H3N0.189 (2)0.184 (3)0.8990 (9)0.021*
N4−0.10824 (17)−0.0767 (2)0.90998 (7)0.0121 (4)
H4N−0.008 (2)−0.108 (3)0.9240 (9)0.018*
H5N−0.139 (2)−0.009 (3)0.9426 (9)0.018*
C1−0.7283 (2)−0.2267 (3)0.96857 (9)0.0139 (4)
C2−0.73259 (19)−0.3166 (3)0.90150 (9)0.0125 (4)
C3−0.59762 (19)−0.4002 (3)0.88233 (9)0.0162 (4)
H3A−0.6191−0.47040.84230.024*
H3C−0.5558−0.48460.91620.024*
H3B−0.5309−0.29950.87620.024*
C40.4116 (2)−0.0067 (3)0.76127 (9)0.0203 (5)
H4A0.5142−0.01620.77190.030*
H4B0.38990.07280.72340.030*
H4C0.3720−0.13190.75230.030*
C50.3476 (2)0.0790 (3)0.81755 (9)0.0124 (4)
C60.1903 (2)0.1255 (3)0.80944 (9)0.0142 (4)
C7−0.01883 (19)0.2223 (3)0.86077 (9)0.0160 (4)
H7A−0.04500.31200.82540.019*
H7B−0.03450.28470.90130.019*
C8−0.1158 (2)0.0483 (3)0.85087 (9)0.0143 (4)
H8A−0.21450.09030.83940.017*
H8B−0.0887−0.02600.81450.017*
C9−0.19929 (19)−0.2503 (3)0.89620 (8)0.0143 (4)
H9A−0.1580−0.32930.86460.017*
H9B−0.2948−0.21180.87700.017*
C10−0.2118 (2)−0.3664 (3)0.95673 (9)0.0171 (4)
H10A−0.2698−0.47890.94490.021*
H10B−0.1167−0.40910.97500.021*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0160 (7)0.0177 (8)0.0139 (7)0.0013 (6)0.0025 (5)−0.0025 (6)
O20.0156 (8)0.0239 (8)0.0132 (7)0.0003 (6)−0.0028 (6)−0.0031 (6)
O30.0161 (8)0.0264 (8)0.0114 (7)0.0014 (7)−0.0003 (6)−0.0043 (6)
O40.0112 (7)0.0286 (9)0.0177 (8)0.0035 (6)−0.0002 (6)−0.0047 (6)
O50.0154 (7)0.0250 (8)0.0127 (7)0.0001 (6)−0.0003 (6)0.0020 (6)
O60.0173 (8)0.0311 (9)0.0157 (7)−0.0033 (7)0.0057 (6)−0.0020 (6)
N10.0193 (9)0.0160 (9)0.0089 (8)−0.0016 (7)0.0030 (7)−0.0017 (7)
N20.0095 (8)0.0173 (9)0.0193 (9)0.0018 (7)0.0022 (7)0.0012 (7)
N30.0117 (9)0.0180 (10)0.0116 (9)−0.0007 (7)−0.0001 (6)−0.0003 (7)
N40.0113 (9)0.0159 (9)0.0094 (8)0.0011 (7)0.0027 (7)−0.0001 (7)
C10.0160 (11)0.0116 (11)0.0141 (10)−0.0007 (8)0.0017 (8)0.0028 (8)
C20.0135 (10)0.0101 (10)0.0139 (10)−0.0010 (8)0.0022 (8)0.0014 (8)
C30.0142 (10)0.0197 (11)0.0146 (10)0.0003 (9)0.0010 (8)−0.0018 (9)
C40.0164 (11)0.0276 (12)0.0167 (11)0.0011 (9)0.0015 (9)−0.0019 (9)
C50.0152 (10)0.0096 (10)0.0126 (10)−0.0005 (8)0.0024 (8)0.0009 (8)
C60.0191 (11)0.0097 (10)0.0138 (10)−0.0026 (8)0.0023 (9)0.0030 (8)
C70.0151 (11)0.0161 (11)0.0175 (11)0.0009 (9)0.0042 (8)0.0016 (8)
C80.0123 (10)0.0192 (12)0.0115 (10)0.0014 (9)0.0017 (8)0.0015 (8)
C90.0131 (10)0.0150 (11)0.0150 (10)−0.0019 (8)0.0022 (8)−0.0019 (8)
C100.0174 (11)0.0174 (11)0.0172 (10)0.0015 (9)0.0047 (8)0.0023 (9)
Geometric parameters (Å, °) top
O1—C11.266 (2)C2—C31.488 (2)
O2—C11.258 (2)C3—H3A0.9600
O3—N11.4095 (18)C3—H3C0.9600
O3—H3O0.90 (2)C3—H3B0.9600
O4—N21.3861 (19)C4—C51.494 (2)
O4—H4O0.95 (2)C4—H4A0.9600
O5—C61.248 (2)C4—H4B0.9600
O6—C101.424 (2)C4—H4C0.9600
O6—H6O0.87 (2)C5—C61.497 (2)
N1—C21.284 (2)C7—C81.518 (2)
N2—C51.281 (2)C7—H7A0.9700
N3—C61.329 (2)C7—H7B0.9700
N3—C71.453 (2)C8—H8A0.9700
N3—H3N0.86 (2)C8—H8B0.9700
N4—C91.491 (2)C9—C101.505 (2)
N4—C81.494 (2)C9—H9A0.9700
N4—H4N0.970 (19)C9—H9B0.9700
N4—H5N0.895 (18)C10—H10A0.9700
C1—C21.515 (2)C10—H10B0.9700
N1—O3—H3O102.4 (12)H4B—C4—H4C109.5
N2—O4—H4O99.8 (12)N2—C5—C4127.62 (17)
C10—O6—H6O110.1 (13)N2—C5—C6113.55 (15)
C2—N1—O3111.74 (14)C4—C5—C6118.83 (16)
C5—N2—O4114.45 (14)O5—C6—N3123.72 (18)
C6—N3—C7121.71 (16)O5—C6—C5119.22 (16)
C6—N3—H3N118.4 (13)N3—C6—C5117.05 (16)
C7—N3—H3N119.8 (13)N3—C7—C8112.78 (15)
C9—N4—C8110.61 (14)N3—C7—H7A109.0
C9—N4—H4N112.3 (11)C8—C7—H7A109.0
C8—N4—H4N108.9 (11)N3—C7—H7B109.0
C9—N4—H5N110.3 (12)C8—C7—H7B109.0
C8—N4—H5N108.5 (12)H7A—C7—H7B107.8
H4N—N4—H5N106.1 (16)N4—C8—C7113.05 (15)
O2—C1—O1125.82 (17)N4—C8—H8A109.0
O2—C1—C2115.20 (16)C7—C8—H8A109.0
O1—C1—C2118.98 (17)N4—C8—H8B109.0
N1—C2—C3126.33 (17)C7—C8—H8B109.0
N1—C2—C1115.17 (16)H8A—C8—H8B107.8
C3—C2—C1118.46 (16)N4—C9—C10112.47 (15)
C2—C3—H3A109.5N4—C9—H9A109.1
C2—C3—H3C109.5C10—C9—H9A109.1
H3A—C3—H3C109.5N4—C9—H9B109.1
C2—C3—H3B109.5C10—C9—H9B109.1
H3A—C3—H3B109.5H9A—C9—H9B107.8
H3C—C3—H3B109.5O6—C10—C9112.58 (15)
C5—C4—H4A109.5O6—C10—H10A109.1
C5—C4—H4B109.5C9—C10—H10A109.1
H4A—C4—H4B109.5O6—C10—H10B109.1
C5—C4—H4C109.5C9—C10—H10B109.1
H4A—C4—H4C109.5H10A—C10—H10B107.8
O3—N1—C2—C3−1.2 (3)N2—C5—C6—O5170.68 (17)
O3—N1—C2—C1176.22 (14)C4—C5—C6—O5−9.1 (3)
O2—C1—C2—N1−174.16 (17)N2—C5—C6—N3−9.8 (2)
O1—C1—C2—N17.0 (2)C4—C5—C6—N3170.42 (17)
O2—C1—C2—C33.4 (2)C6—N3—C7—C873.0 (2)
O1—C1—C2—C3−175.41 (17)C9—N4—C8—C7−176.88 (15)
O4—N2—C5—C40.4 (3)N3—C7—C8—N472.22 (18)
O4—N2—C5—C6−179.41 (14)C8—N4—C9—C10−171.87 (14)
C7—N3—C6—O5−0.2 (3)N4—C9—C10—O660.2 (2)
C7—N3—C6—C5−179.75 (16)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O3—H3O···O5i0.90 (2)1.78 (2)2.677 (2)173 (2)
O4—H4O···O2ii0.95 (2)1.63 (2)2.5733 (18)172.3 (19)
O6—H6O···O20.87 (2)2.25 (2)3.101 (2)163.4 (18)
N3—H3N···O6ii0.86 (2)2.11 (2)2.940 (2)162.6 (18)
N4—H4N···O1iii0.970 (19)1.93 (2)2.838 (2)155.1 (15)
N4—H5N···O1iv0.895 (18)1.921 (19)2.796 (2)165.1 (17)
Symmetry codes: (i) −x−1, y−1/2, −z+3/2; (ii) −x, −y, −z+2; (iii) x+1, y, z; (iv) −x−1, −y, −z+2.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
O3—H3O···O5i0.90 (2)1.78 (2)2.677 (2)173 (2)
O4—H4O···O2ii0.95 (2)1.63 (2)2.5733 (18)172.3 (19)
O6—H6O···O20.87 (2)2.25 (2)3.101 (2)163.4 (18)
N3—H3N···O6ii0.86 (2)2.11 (2)2.940 (2)162.6 (18)
N4—H4N···O1iii0.970 (19)1.93 (2)2.838 (2)155.1 (15)
N4—H5N···O1iv0.895 (18)1.921 (19)2.796 (2)165.1 (17)
Symmetry codes: (i) −x−1, y−1/2, −z+3/2; (ii) −x, −y, −z+2; (iii) x+1, y, z; (iv) −x−1, −y, −z+2.
Acknowledgements top

The authors thank the Ministry of Education and Science of Ukraine for financial support (grant No. F28/241–2009).

references
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