ChemInform Abstract: Triniobium Polytungstophosphates. Syntheses, Structures, Clarification of Isomerism and Reactivity in the Presence of H2O2.

✍ Scribed by M. K. HARRUP; G.-S. KIM; H. ZENG; R. P. JOHNSON; D. VANDERVEER; C. L. HILL

• Publisher: John Wiley and Sons
• Year: 2010
• Weight: 39 KB
• Volume: 30
• Category: Article
• ISSN: 0931-7597
• DOI: 10.1002/chin.199901019

✦ Synopsis

Triniobium Polytungstophosphates. Syntheses, Structures, Clarification of Isomerism and Reactivity in the Presence of H 2 O 2 . -The new tris(peroxoniobium) monomer [(NbO 2 ) 3 PW 9 O 37 ] 6-(IV) is synthesized and converted into the novel monomer [Nb 3 PW 9 O 40 ] 6-(V) and the dimer [Nb 6 P 2 W 18 O 77 ] 6-(VI). An X-ray structure analysis on the Cs salt of (IV) (monoclinic, space group P2/c, Z = 4) confirms the A-type substitution pattern of the three Nb atoms and clarifies the M 3 rotational isomerism in the Keggin unit as β. The Bu 4 N + salt (IV) proves to be an efficient catalyst for the selective peroxide oxidation of olefins into vicinal diols. Much of the catalytic activity is referred to the generation of tungstate under the reaction condition. -