Applications of molybdenum-95 NMR spectroscopy. 7. Studies of metal-metal bonded systems including aqueous molybdenum(IV) and molybdenum(V). Crystal and molecular structure of Na/sub 2/(Mo/sub 3/O/sub 4/((O/sub 2/CCH/sub 2/)/sub 2/NCH/sub 3/)/sub 3/). 7H/sub 2/O
- La Trobe Univ., Bundoora, Victoria, Australia
Solution /sup 95/Mo NMR studies are reported on spin-coupled polynuclear systems of Mo(V), Mo(IV), and Mo(II). Resonances occur at low fields compared to mononuclear species. The chemical shifts of the Mo(IV)-aquo ion in 4 M p-toluenesulfonic and methanesulfonic acid media and those of the Mo(IV) complexes containing oxalate, EDTA, and methyliminodiacetate ligands (whose solid-state structures are based on the (Mo/sub 3/O/sub 4/)/sup 4 +/ cluster) fall in the narrow range of 172 ppm spanning 990-1162 ppm. As the known chemical shift scale for the /sup 95/Mo nucleus covers 7000 ppm, this observation indicates that the /sup 95/Mo nucleus is in a similar chemical environment in each of the species examined and, taken with published evidence, confirms formulation of the Mo(IV)-aquo ion as (Mo/sub 3/O/sub 4/(H/sub 2/O)/sub 9/)/sup 4 +/. Two resonances are detected in the above range for Mo(IV)/sub aq/ in 4 M hydrochloric acid and for ((Mo/sub 3/O/sub 4/)/sub 2/(PDTA)/sub 3/)/sup 4 -/. Additional resonances appear at 539-608 ppm in the methanesulfonic acid, hydrochloric acid, and EDTA systems when stored in air. These are assigned to (Mo/sup v//sub 2/O/sub 4/)/sup 2 +/-based species by comparison with the observed resonances of the Mo(V)-aquo ion, (Mo/sup v//sub 2/O/sub 4/(H/sub 2/O)/sub 6/)/sup 2 +/, in the relevant acid media and with (Mo/sup v//sub 2/O/sub 4/(EDTA))/sup 2 -/ in H/sub 2/O. The (Mo/sup v//sub 2/O/sub 4/(PDTA))/sup 2 -/ anion exhibits two resonances associated with inequivalent molybdenum sites. Resonances for (Mo/sup II//sub 2/(O/sub 2/CR)/sub 4/) (R = CF/sub 3/, n-Pr), which contain formal quadruple bonds, have been observed for the first time and are the most deshielded /sup 95/Mo NMR signals detected to date. The methyliminodiacetate complex, Na/sub 2/(Mo/sub 3/O/sub 4/((O/sub 2/CCH/sub 2/)/sub 2/NCH/sub 3/)/sub 3/).7H/sub 2/O, was isolated. Its crystal structure contains a discrete trinuclear (Mo/sup IV//sub 3/O/sub 4/((O/sub 2/CCH/sub 2/)/sub 2/NCH/sub 3/)/sub 3/)/sup 2 -/ anion whose symmetry approaches C/sub 3v/.
- OSTI ID:
- 5486606
- Journal Information:
- J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 105:6; ISSN JACSA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Preparation and characterization of binuclear complexes of molybdenum(III) and molybdenum(V) via oxidative decarbonylation. Reactions of LMo(CO)/sub 3/ (L = 1,5,9-triazacyclododecane) and crystal structure of anti-(L/sub 2/Mo/sub 2/O/sub 4/)(ClO/sub 4/)/sub 2/ x 2H/sub 2/O
Molybdenum binding site models for the molybdenum cofactor. Synthesis, spectroscopic characterization, and EHMO analysis of (NBu[sup n][sub 4])Na[Mo(O[sub 2]CC(S)Ph[sub 2])[sub 3]]
Related Subjects
400104* -- Spectral Procedures-- (-1987)
ALKALI METAL COMPOUNDS
CHEMICAL BONDS
COMPLEXES
ENERGY LEVELS
EVEN-ODD NUCLEI
INTERMEDIATE MASS NUCLEI
ISOTOPES
LIGANDS
MAGNETIC RESONANCE
MOLYBDENUM 95
MOLYBDENUM COMPLEXES
MOLYBDENUM ISOTOPES
NUCLEAR MAGNETIC RESONANCE
NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
ORGANOMETALLIC COMPOUNDS
ORIENTATION
RESONANCE
SODIUM COMPOUNDS
SPIN ORIENTATION
STABLE ISOTOPES
STRUCTURAL CHEMICAL ANALYSIS
SULFONIC ACIDS
TRANSITION ELEMENT COMPLEXES