Synthesis and Structure of a Sodium Complex of an Aromatic β-Diketone and Pyrazolylpyridine

Molecules

Ana C. Coelho¹  Filipe A. Almeida Paz¹  Jacek Klinowski¹  Martyn Pillinger¹ 

[1] ¹Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal ²Department of Chemistry, University of Cambridge, Lensfield Road, CB2 1EW, Cambridge, UK

关键词: Sodium;    bridging ligands;    N ligands;    O ligands;    coordination modes;    aggregation;   

DOI  :  10.3390/molecules11070528

来源: mdpi

【 摘 要 】

Reaction of NaH with a THF solution of Eu(BTA)3(pypzH) [BTA = 1-benzoyl-3,3,3-trifluoroacetonate, pypzH = 2-(3-pyrazolyl)pyridine] leads to the formation of theeuropium-free tetrasodium complex [Na₄(pypzH)₂(μ4-BTA)₂(μ2-BTA)₂]. Single-crystal X-ray diffraction studies revealed the presence of a centrosymmetric Na hybrid tetramer,which fully occupies the contents of the triclinic unit cell. The crystal structure containstwo individual Na cations, Na(1) and Na(2), which have highly irregular {NaN₂O₃} and{NaO₆} local coordination environments, respectively. One of the key features is thepresence of a central {Na₄O₆} core, which is unprecedented for Na . Externally to this{Na₄O₆} cluster pyrazolylpyridine organic molecules are N,N-chelated to Na(1). Eventhough all of the organic residues contain aromatic rings, the crystal packing of individualcentrosymmetric tetrasodium [Na₄(pypzH)₂(μ4-BTA)₂(μ2-BTA)₂] molecular moieties isessentially driven through geometrical aspects combined with weak C–H···π interactions,rather than the expected a priori π-π interactions. The material also contains classicalstrong hydrogen bonds, even though these do not directly contribute to the packingdriving forces.

【 授权许可】

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