Synthesis and structure of a sodium complex of an aromatic beta-diketone and pyrazolylpyridine.
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 the europium-free tetrasodium complex [Na(4)(pypzH)(2)(micro4-BTA)(2)(micro2-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 contains two individual Na+ cations, Na(1) and Na(2), which have highly irregular [NaN(2)O(3)] and[NaO(6)] local coordination environments, respectively. One of the key features is the presence of a central [Na(4)O(6)] core, which is unprecedented for Na+ . Externally to this [Na(4)O(6)] cluster pyrazolylpyridine organic molecules are N,N-chelated to Na(1). Even though all of the organic residues contain aromatic rings, the crystal packing of individual centrosymmetric tetrasodium [Na(4)(pypzH)(2)(micro4-BTA)(2)(micro2-BTA)(2)] molecular moieties is essentially driven through geometrical aspects combined with weak C-H...pi interactions, rather than the expected a priori pi-pi interactions. The material also contains classical strong hydrogen bonds, even though these do not directly contribute to the packing driving forces.
Coelho
Ana C
AC
Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal. igoncalves@dq.ua.pt.
Paz
Filipe A Almeida
FA
Klinowski
Jacek
J
Pillinger
Martyn
M
Gonçalves
Isabel S
IS
D002614:Chelating Agents / Q000737:chemistry; D003460:Crystallization; D007659:Ketones / Q000737:chemistry*; D008024:Ligands; D011720:Pyrazoles / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry*; D012964:Sodium / Q000737:chemistry*; D014961:X-Ray Diffraction
D002614:Chelating Agents; D007659:Ketones; D008024:Ligands; D011720:Pyrazoles; D011725:Pyridines; C118531:pyrazolopyridine; D012964:Sodium