Poly[diaquabis­(μ4-fumarato-κ4 O 1:O 1′:O 4:O 4′)(μ4-fumarato-κ6 O 1:O 1,O 1′:O 4:O 4,O 4′)(μ2-fumaric acid-κ2 O 1:O 4)dipraseodymium(III)]

Pei-lian Liu; Wanwan Cao; Jin Wang; Rong-hua Zeng; Zhuo Zeng

doi:10.1107/S1600536811038347

. 2011 Sep 30;67(Pt 10):m1433–m1434. doi: 10.1107/S1600536811038347

Poly[diaquabis(μ₄-fumarato-κ⁴ O ¹:O ^1′:O ⁴:O ^4′)(μ₄-fumarato-κ⁶ O ¹:O ¹,O ^1′:O ⁴:O ⁴,O ^4′)(μ₂-fumaric acid-κ² O ¹:O ⁴)dipraseodymium(III)]

Pei-lian Liu ^a, Wanwan Cao ^a, Jin Wang ^a, Rong-hua Zeng ^a, Zhuo Zeng ^a,^b,^*

PMCID: PMC3201313 PMID: 22058712

Abstract

The title complex, [Pr₂(C₄H₂O₄)₃(C₄H₄O₄)(H₂O)₂]_n, was synthesized by reaction of praseodymium(III) nitrate hexahydrate with fumaric acid in a water–ethanol (4:1) solution. The asymmetric unit comprises a Pr³⁺ cation, one and a half fumarate dianions (L ²⁻), one half-molecule of fumaric acid (H₂L) and one coordinated water molecule. The carboxylate groups of the fumarate dianion and fumaric acid exhibit different coordination modes. In one fumarate dianion, two carboxylate groups are chelating with two Pr³⁺ cations, and the other two O atoms each coordinate a Pr³⁺ cation. Each O atom of the second fumarate dianion binds to a different Pr³⁺ cation. The fumaric acid employs one O atom at each end to bridge two Pr³⁺ cations. The Pr³⁺ cation is coordinated in a distorted tricapped trigonal–prismatic environment by eight O atoms of fumarate dianion or fumaric acid ligands and one water O atom. The PrO₉ coordination polyhedra are edge-shared through one carboxylate O atom and two carboxylate groups, generating infinite praseodymium–oxygen chains, which are further connected by the ligands into a three-dimensional framework. The crystal structure is stabilized by O—H⋯O hydrogen-bond interactions between the coordinated water molecule and the carboxylate O atoms.

Related literature

For the structural diversity and potential use as superconductors and magnetic materials of metal complexes of carboxylates, see: Kim et al. (2004 ▶); Ye et al. (2005 ▶). For applications of rare earth carboxylates, see: Baggio & Perec (2004 ▶); Seo et al. (2000 ▶).

Experimental

Crystal data

[Pr₂(C₄H₂O₄)₃(C₄H₄O₄)(H₂O)_2]]
M _r = 776.10
Monoclinic,
a = 8.3714 (3) Å
b = 14.6034 (6) Å
c = 8.7518 (4) Å
β = 103.118 (2)°
V = 1042.00 (7) Å³
Z = 2
Mo Kα radiation
μ = 4.72 mm⁻¹
T = 298 K
0.26 × 0.19 × 0.15 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ▶) T _min = 0.355, T _max = 0.493
10102 measured reflections
2394 independent reflections
2175 reflections with I > 2σ(I)
R _int = 0.027

Refinement

R[F ² > 2σ(F ²)] = 0.016
wR(F ²) = 0.041
S = 1.05
2394 reflections
170 parameters
3 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.44 e Å⁻³
Δρ_min = −0.75 e Å⁻³

Data collection: APEX2 (Bruker, 2008 ▶); cell refinement: SAINT (Bruker, 2008 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXL97.

Supplementary Material

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536811038347/hg5089sup1.cif

e-67-m1433-sup1.cif^{(19.9KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536811038347/hg5089Isup2.hkl

e-67-m1433-Isup2.hkl^{(114.5KB, 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
C3—H3⋯O7	0.93	2.50	2.815 (3)	100
O1W—H2W⋯O7ⁱ	0.83 (1)	2.11 (1)	2.911 (2)	165 (2)
O2—H2A⋯O9ⁱⁱ	0.82	1.86	2.661 (2)	167
O1W—H1W⋯O5ⁱⁱⁱ	0.82 (1)	2.09 (2)	2.816 (2)	147 (2)

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

Acknowledgments

The authors gratefully acknowledge the support of the Department of Science and Technology, Guangdong Province [grant Nos. 2010 A020507001–76, 5300410, FIPL-05–003].

supplementary crystallographic information

Comment

Metal complexes of carboxylates have attracted much attention due to their wide range of structural diversities and potential use on superconductors and magnetic materials (Kim et al., 2004; Ye et al., 2005). What is more, a particularly attractive goal is the rare-earth carboxylates, because of their special application on the 4f-block elements and their unique f-f electronic transitions. (Seo et al., 2000; Baggio et al., 2004). In this paper, we report the title complex (scheme. 1), obtained by the reaction of praseodymium(III) nitrate hexahydrate with fumaric acid in a water-ethanol (4:1) solution.

The structure of the asymmetric unit of the title complex is shown in Fig. 1. It comprises a Pr³⁺ cation, 1.5 fumarate dianions (L^2-), 0.5 fumaric acid (H₂L) and one water ligand. The carboxylate groups of the fumarate dianion and fumaric acid exhibit different coordination modes. In one fumarate dianion, two carboxylate groups are chelating with two Pr³⁺ cations, and other two O atoms(O4 and O4^iv) are coordinated with Pr³⁺ cation respectively. The other fumarate dianion bridges four Pr³⁺ cations with monodentate mode, and the fumaric acid bridges two Pr³⁺ cations with monodentate mode. In the crystallographic asymmetric unit, the Pr³⁺ cation is sited within a distorted tricapped trigonal prism defined by nine O atoms derived from seven different bridging ligands and a coordinated water molecule. One of the carboxylate groups, derived from L^2-, is chelating, and the remaining six carboxylates coordinate in a monodentate mode. The Pr—O bond distances range from 2.4040 (15) to 2.7719 (16) Å. The O—Pr—O bond angles range from 72.35 (5) to 146.04 (5)°. The PrO₉ coordination polyhedra are edge-shared through one carboxylate O atoms (O4) and two carboxylate groups (O8—C4—O9 and O6—C1—O7) to generate infinite praseodymium-oxygen chains (Fig. 2). The chains are further connected by the ligands to form a three-dimensional framework. The crystal is stabilized by hydrogen bond interactions between the coordinated water and carboxylate O atoms.

Experimental

Fumaric acid (0.5 mmol, 0.058 g), Praseodymium(III) nitrate hexahydrate(0.3 mmol, 0.13 g) was dissolved in a water-ethanol(4:1) solution(10 ml). The mixture was transferred to a 20 ml Teflon-lined stainless steel autoclave, which was heated at 413 K for 96 h. The reactor was cooled to room temperature over a period of 24 h. Blue crystals were obtained after filtrated, washed with water and vacuum dried.