Bis[2-(2-hy­droxy­meth­yl)pyridine-κ2 N,O](pivalato-κO)copper(II)

M Mobin Shaikh; Veenu Mishra; Priti Ram; Anil Birla

doi:10.1107/S1600536812030917

. 2012 Jul 14;68(Pt 8):m1055. doi: 10.1107/S1600536812030917

Bis[2-(2-hydroxymethyl)pyridine-κ² N,O](pivalato-κO)copper(II)

M Mobin Shaikh ^a,^*, Veenu Mishra ^a, Priti Ram ^a, Anil Birla ^a

PMCID: PMC3414121 PMID: 22904728

Abstract

The structure of the centrosymmetric title complex, [Cu(C₅H₉O₂)₂(C₆H₇NO)₂], has the Cu^II atom on a centre of inversion. The Cu^II atom is six-coordinate with a distorted octahedral geometry, defined by the N and O atoms of the chelating 2-(2-hydroxymethyl)pyridine ligands and two carboxylate O atoms from two monodentate pivalate ions. The crystal packing is stabilized by intermolecular C—H⋯O and intramolecular O—H⋯O hydrogen-bond interactions.

Related literature

For pyridine alcohol-based biomimetic sensors, see: Shaikh et al. (2010 ▶). For solid-state transformations, see: Shaikh et al. (2009 ▶, 2010 ▶). For structures with pyridine alcohols, see: Hamamci et al. (2004 ▶); Lah et al. (2006 ▶).

Experimental

Crystal data

[Cu(C₅H₉O₂)₂(C₆H₇NO)₂]
M _r = 484.04
Monoclinic,
a = 9.797 (5) Å
b = 8.829 (5) Å
c = 13.674 (5) Å
β = 91.907 (5)°
V = 1182.1 (10) Å³
Z = 2
Cu Kα radiation
μ = 1.63 mm⁻¹
T = 150 K
0.33 × 0.28 × 0.23 mm

Data collection

Oxford Super Nova diffractometer
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009 ▶) T _min = 0.615, T _max = 0.706
6929 measured reflections
2282 independent reflections
2052 reflections with I > 2σ(I)
R _int = 0.036

Refinement

R[F ² > 2σ(F ²)] = 0.040
wR(F ²) = 0.119
S = 1.06
2282 reflections
146 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.43 e Å⁻³
Δρ_min = −0.54 e Å⁻³

Data collection: CrysAlis CCD (Oxford Diffraction, 2009 ▶); cell refinement: CrysAlis CCD; data reduction: CrysAlis RED (Oxford Diffraction, 2009 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: DIAMOND (Brandenburg, 1999 ▶); software used to prepare material for publication: publCIF (Westrip, 2010 ▶).

Supplementary Material

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536812030917/bt5967sup1.cif

e-68-m1055-sup1.cif^{(23.6KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812030917/bt5967Isup2.hkl

e-68-m1055-Isup2.hkl^{(109.9KB, hkl)}

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

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H101⋯O3	0.95 (4)	1.64 (4)	2.588 (2)	171 (3)
C2—H2⋯O3ⁱ	0.95	2.57	3.289 (3)	132
C4—H4⋯O3ⁱⁱ	0.95	2.50	3.392 (3)	157

Open in a new tab

Symmetry codes: (i) Inline graphic ; (ii) .

Acknowledgments

The authors gratefully acknowledge the IIT Indore–Agilent Technologies–Aimil Summer Fellowship Programme on X-ray Crystallography. PR and AB would like to thank Agilent Technologies and Aimil Ltd for providing the fellowship. The authors acknowledge the Single-Crystal Diffraction Facility at the Sophisticated X-ray Instrumentation Centre (SIC), IIT Indore.

supplementary crystallographic information

Comment

We have reported a series of pyridine alcohol based Cu(II) complexes with a range of applications such as biomimetic sensors (Shaikh et al., 2010) and solid-state transformations (Shaikh et al., 2009). Pyridine alcohols are used because they possess two functional groups, both having the ability to bind the metal centres (Hamamci et al., 2004; Lah et al., 2006).

Herein we report synthesis and crystal structure of a mononuclear Cu(II) complex with hmp-H acting as a bidentate chelating ligand. The Cu(II) atom is surrounded by two N and O atoms from hmp-H in a basal plane and the apical positions are occupied by two O atoms from monodentate pivalate group forming a distorted octahedral geometry (Fig. 1).

The packing reveals intra (O—H···O) and inter (C—H···O) hydrogen bonds. The intramolecular hydrogen bonding involves the alcoholic OH group of hmp-H and an O atom of the pivalate group (Fig. 2). The intermolecular C(4)—H(4)···.O(3) hydrogen bond involves an H-atom of pyridine ring and an O atom of the pivalate group forming one-dimensional chain along the b-axis which binds to a neighbouring one-dimensional chain via C(2)—H(2)···O(3) along c-axis, leading to the formation of hydrogen bonded two-dimensional network (Fig. 3).

Experimental

A solution of pivalic acid (102 mg, 1.0 mmol) in 10 ml methanol was added to a 30 ml methanolic solution of Cu(CH₃COO)₂.2H₂O (199 mg, 1.0 mmol) and hmp-H (109 mg, 1.0 mmol). The resultant solution was stirred for 12 h at room temperature. The solution was then passed through filter paper (Whatman filter paper, 70 mm) in order to remove any unreacted materials. The filtrate was allowed to stand at room temperature for crystallization. On slow evaporation light-blue single crystals of [Cu(C₅H₇ON)₂(C₅H₉O₂)₂] were obtained after 2–3 d. M.p. 476–478 K. Yield: 88%. Anal. Calcd for C₂₂H₃₂CuN₂O₆ (Mr = 484.04): C, 54.59; H, 6.66; N, 5.79. Found: C 54.62; H 6.70; N 5.76.