MOLMAT 2010 Conference, July 5-8, 2010, Montpellier, France
Zirconium and hafnium coordination compounds with 1,4-dihydroxy-2,5-benzoquinone
M. Boltoeva, J. Maynadie, D. Meyer
Institut de Chimie Séparative de Marcoule/ Centre de Marcoule, BP 17171, 30207 Bagnols-sur-Céze Cedex, France
maria.boltoeva@cea.fr
The design and synthesis of multifunctional compounds and materials with predictable structure and
properties are one of the topical fields in modern chemistry. The molecular building block approach is
now of great interest in the construction of polymeric coordination architectures. These polymers
consisting of metal ions and organic ligands as bridges are very promising for processability, flexibility,
structural diversity, and geometrical (size, shape, and symmetry) control [1, 2].
Oxocarbon is considered to be one of the most useful multifunctional ligand families. 1,4-dihydroxy-2,5benzoquinone (H2Dhbq) and its derivatives possess coordination, hydrogen bonding and ionic interaction
sites, together with redox active π-electronic structures, affording rich coordination chemistry [3].
Although a number of coordination polymers involving Dhbq2- as a bridging ligand have already been
reported, our work directed at the synthesis and characterization of new polymeric precursors to ceramic
materials is presented.
In the present study, we synthesized a series of the zirconium(IV) and hafnium(IV) complexes with
Dhbq2- under different experimental conditions. Then, the mixed Zr(IV)/Hf(IV) complexes with various
ratios of the metals were prepared. The analytical techniques used were elemental analysis, FTIR and Xray powder diffraction.
It was found that the synthesis conditions, namely the nature of the solvent and the temperature are
important factors in the complex formation. IR-absorption spectral data indicate the bonding of hydroxyl
oxygen and quinone carbonyls with metal ions. The tentative structure of the polymers of Zr(IV) with
1,4-dihydroxy-2,5-benzoquinone is assigned in Scheme 1.
O
3+
Zr
Cl
O
O
O
O
Zr
Cl
O
O
3+
Zr
O
Scheme 1. Structure of coordination polymer of Zr(IV) with 1,4-dihydroxy-2,5-benzoquinone
The characterization of obtained complexes by solid-state NMR technique and thermal studies are
currently in progress. The preliminary results obtained show that the synthesized compounds are
convenient precursors for ceramic materials.
The further studies will be performed with metals in various oxidation states (III, IV and V) in order to
obtain the mixed valence complexes.
References
[1] O.M Yaghi et al., Acc.Chem. Res. 34, 319 (2001).
[2] B.H. Ye et al., Coord. Chem. Rev. 249, 545 (2005).
[3] S. Kitagawa et al., Coord. Chem. Rev. 224, 11 (2002).