Aqua­(1,10-phenanthroline-κ2 N,N′)(valinato-κ2 N,O)copper(II) nitrate dihydrate

Araceli Tovar-Tovar; Juan-Carlos García-Ramos; Marcos Flores-Alamo; Lena Ruiz-Azuara

doi:10.1107/S1600536811047398

. 2011 Nov 23;67(Pt 12):m1796–m1797. doi: 10.1107/S1600536811047398

Aqua(1,10-phenanthroline-κ² N,N′)(valinato-κ² N,O)copper(II) nitrate dihydrate

Araceli Tovar-Tovar ^a, Juan-Carlos García-Ramos ^a, Marcos Flores-Alamo ^a,^*, Lena Ruiz-Azuara ^a

PMCID: PMC3238705 PMID: 22199582

Abstract

In the title compound, [Cu(C₅H₁₀NO₂)(C₁₂H₈N₂)(H₂O)]NO₃·2H₂O, the Cu^II atom displays a distorted square-pyramidal coordination (τ = 0.03) where the water molecule occupies the apical position and the base is defined by the N atom, one of the O atoms from the valinate ligand, and both phenanthroline N atoms. The phenanthroline chelate ring plane is slightly distorted from planarity (r.m.s. deviation = 0.0057 Å), whereas the five-membered ring formed by the valinate ligand presents an envelope conformation with the N atom being the flap atom. The crystal packing is stabilized by O—H⋯O and N—H⋯O hydrogen-bonding interactions, creating a three-dimensional network superstructure.

Related literature

For investigations related to anticancer compounds, see: Ruiz-Azuara (1996 ▶, 1997 ▶). For a description of the geometry of complexes with five-coordinate Cu^II atoms, see: Rao et al. (1981 ▶); Addison et al. (1984 ▶); Le et al. (2006 ▶); Dalhus & Görbitz (1999 ▶).

Experimental

Crystal data

[Cu(C₅H₁₀NO₂)(C₁₂H₈N₂)(H₂O)]NO₃·2H₂O
M _r = 475.94
Triclinic,
a = 7.9020 (19) Å
b = 9.610 (3) Å
c = 14.327 (4) Å
α = 81.89 (3)°
β = 75.04 (2)°
γ = 87.92 (2)°
V = 1040.6 (5) Å³
Z = 2
Mo Kα radiation
μ = 1.10 mm⁻¹
T = 298 K
0.45 × 0.27 × 0.21 mm

Data collection

Siemens P4 diffractometer
Absorption correction: ψ scan (XSCANS; Siemens, 1993 ▶) T _min = 0.729, T _max = 0.794
5563 measured reflections
4551 independent reflections
3807 reflections with I > 2σ(I)
R _int = 0.024
3 standard reflections every 97 reflections intensity decay: 4.9%

Refinement

R[F ² > 2σ(F ²)] = 0.037
wR(F ²) = 0.094
S = 1.06
4551 reflections
297 parameters
18 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.45 e Å⁻³
Δρ_min = −0.33 e Å⁻³

Data collection: XSCANS (Siemens, 1993 ▶); cell refinement: XSCANS; data reduction: XSCANS; 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: WinGX (Farrugia, 1999 ▶).

Supplementary Material

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536811047398/jj2109sup1.cif

e-67-m1796-sup1.cif^{(22.8KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536811047398/jj2109Isup2.hkl

e-67-m1796-Isup2.hkl^{(218.4KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Selected bond lengths (Å).

Cu1—N1	2.0320 (19)
Cu1—N2	1.9975 (19)
Cu1—N3	1.992 (2)
Cu1—O2	1.9349 (16)
Cu1—O3W	2.263 (2)

Open in a new tab

Table 2. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3W—H3A⋯O1W	0.83 (2)	2.02 (2)	2.778 (3)	153 (3)
N3—H01⋯O1W	0.87 (3)	2.15 (3)	2.967 (4)	156 (2)
O3W—H3B⋯O2W	0.84 (2)	1.92 (2)	2.753 (3)	171 (3)
O1W—H1A⋯O4ⁱ	0.80 (2)	2.02 (2)	2.810 (4)	170 (3)
O1W—H1B⋯O4ⁱⁱ	0.82 (2)	2.19 (2)	2.881 (4)	143 (2)
O1W—H1B⋯O5ⁱⁱ	0.82 (2)	2.48 (2)	3.245 (5)	156 (3)
O2W—H2A⋯O1ⁱⁱⁱ	0.80 (2)	2.05 (2)	2.836 (3)	167 (3)
O2W—H2B⋯O1^iv	0.84 (2)	2.02 (2)	2.851 (3)	174 (3)
N3—H02⋯O3^v	0.82 (3)	2.46 (3)	3.229 (4)	158 (2)
N3—H02⋯O5^v	0.82 (3)	2.58 (3)	3.168 (4)	130 (2)

Open in a new tab

Symmetry codes: (i) Inline graphic ; (ii) ; (iii) ; (iv) ; (v) .

Acknowledgments

We thank CONACYT 87806, PAPIIT IN 227110 and PICSA10–61 for their financial support of this work. MFA is indebted to Dr A. L. Maldonado-Hermenegildo for useful comments.

supplementary crystallographic information

Comment

Investigations related to anticancer compounds (Ruiz-Azuara, 1996; 1997) that involve essential metals has been of considerable interest during the last three decades. In this context, we have prepared and crystallized the complex [Cu(H₂O)(val)(phen)]NO₃. 2H₂O (val is valinate and phen is 1,10-phenantroline), (I).

The asymmetric unit consists of one [Cu(H₂O)(val)(phen)] cationic complex, one nitrate anion and two water molecules. The metallic centre display a distorted square-pyramidal coordination (τ =0.03) where the water molecule occupies the apical position. The base is defined by the N and one of the O atoms from the valinate ligand, and both phenanthroline N atoms. The phenanthroline chelate-ring plane is slightly distorted from planarity (r.m.s. = 0.0057), whereas the five-membered ring formed by the valine ligand (defined by atoms N3, C14, C13, O2 and Cu), presents an envelope conformation on N3 (q2 = 0.2121 and φ = 141.74 °) (Rao et al., 1981). The Cu^II ion coordinates two nitrogen atoms of phen and the amino nitrogen and one carboxylate oxygen atoms of L-Val [Cu1–N1 = 2.0320 (19), Cu1–N2 = 1.9975 (19), Cu1–N3 = 1.992 (2), and Cu1–O2 = 1.9349 (16) Å], while one water oxygen atom is axial [Cu1–O3w = 2.263 (2) Å]. The resulting coordination geometries are in a distorted square-pyramidal orientation (figure 1), where N1,N2, N3, O2 and Cu1 for the complex deviate by -0.0079, 0.0085, -0.0085, 0.0079 and 0.2064 Å, respectively, from the least-squares plane (0.84710x+0.53076y+0.02687z = 12.60140) defined by the four ligating atoms N1,N2, N3, and O2. This indicates that the five atoms in the equatorial positions are approximately coplanar with τ of 0.03 (Addison, et al., 1984). The bond angles observed around the central Cu atom range from 82.13 (8) – 99.01 (8)° in equatorial positions and from 93.90 (8) – 98.54 (8)° for apical positions, showing the angle variability in the geometry adopted by the five coordinate Cu^II complexe (Le et al., 2006). The carboxyl group of the amino acid coordinates to Cu^IIvia one oxygen atom as an unidentate group. Electron delocalization has been observed in the carboxyl group. However, the bond distances (1.270 (3) Å) between the coordinated oxygen atoms and the carbon atoms are slightly longer (1.254 Å) than those between the uncoordinated oxygen atoms and the carbon atoms as expected (Dalhus & Görbitz, 1999).

The nitrate ion and two water molecules are not involved in the coordination sphere of the Cu ion, but are in the crystal lattice. In the supramolecular network there are O—H···O and N—H···O hydrogen bond interactions and weak O—H···O and N—H···O intermolecular interactions (table 1) that help stabilize crystal packing. The O1w donor-acceptor atom of water molecule solvate interacts with O4 acceptor atom of the nitrate group and the N3 donor atom of the amino group, forming R₄²(6) and 2R₂¹(6) motifs, respectively. In addition the hydrogen bond formed from the O3w donor atom of the water coordinated to the metal and O2w donor-acceptor atom of the water solvate and O1 acceptor atom of carboxylate group form a C₂²(5) motif. All these interactions lead to infinite three-dimensional network superstructure with base vectors: #1 = [0 1 0], #2 = [1 0 0], #3 = [0 0 1].

Experimental

1 mmol (0.232 g) of hemi-pentahydrated Cu(NO₃)₂ was dissolved in 5 ml of water and mixed with the corresponding amount of 1,10-phenanthroline (1 mmol, 0.180 g) previously dissolved in alcohol (5 ml). To the resulting a deprotonated solution (10 ml) of L-valine (1 mmol, 0.117 g) was added under constant stirring to get a deep-blue product. Further purification was done washing the solid several times with water. The solid was isolated with 95% yield. Single crystals suitable for X-ray diffraction were obtained by slow evaporation of MeOH. Anal. calcd. for C₁₇H₂₄N₄O₈Cu (475.94 g/mol): C, 42.90; H, 5.08; N, 11.77. Found: C, 42.53; H, 5.11; N, 11.81.