Cyclo-Tetra -μ- oxido-tetrakis[(acetyl-acetonato-κ2 O,O′)bis-(ethanolato-κO)niobium(V)]

Abstract

The asymmetric unit of the title tetra-nuclear niobium(V) compound, [Nb4(C2H5O)8(C5H 7O2)4O4], contains two Nb V atoms, two bridging O atoms, two acetyl-acetonate and four ethano-late ligands. Each NbV atom is six-coordinated by the bridging O atoms, two ethano-late and one chelating acetyl-acetonate ligands. The Nb - O distances vary between 1.817 (2) and 2.201 (2) Å and the O - Nb - O angles vary between 78.88 (8) and 102.78 (9)°, illustrating the significant distortion from ideal ocahedral geometry. The rest of the tetra-nuclear unit is generated through an inversion centre. The C atoms of two of the ethano-late molecules are disordered over two sites [occupancy ratio 0.601 (12):0.399 (12)].