| Popis: |
Investigation on the aqueous coordination chemistry of nitrilotriacetato molybdate (VI) resulted in the isolation of molybdenum(VI) nitrilotriacetato complexes Na6n{[Mo2O5(ntaH)2][(nta)2Mo2O5]}n · 12nH2O (1) and (NH4)3n[Mo2O5H(nta)2]n · 4nH2O (2) (H3nta = nitrilotriacetic acid). The complexes have been characterized by elemental analyses, IR, NMR spectroscopies and X-ray structural analyses. The anions of complexes 1 and 2 contain a linear (O2Mo)O(MoO2) core with the bridging oxo group lying at a center of symmetry. Each molybdenum atom is octahedrally coordinated by two terminal oxo groups, a bridging oxygen and a tridentate nitrilotriacetate ligand, which binds through the nitrogen atom and two μ-O carboxylates, while the other carboxylate remains free. Strong hydrogen bonds are found to exist in the two complexes. This is supported by IR and NMR spectra, and revealed by single crystal X-ray analysis. The complexes 1 and 2 show obvious decomposition in solution based on 13C NMR observations. |
Full Text from ScienceDirect