Hydroxylation of Alkanes with Molecular Oxygen Catalyzed by a New Ruthenium-Substituted Polyoxometalate, [WZnRu(OH)(H2O)(ZnW9O34)2]11−
✍ Scribed by Dr. Ronny Neumann; Dr. Alexander M. Khenkin; Mazal Dahan
- Publisher
- John Wiley and Sons
- Year
- 1995
- Tongue
- English
- Weight
- 380 KB
- Volume
- 34
- Category
- Article
- ISSN
- 0044-8249
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✦ Synopsis
than the fluorine atoms because of its partial double-bond character: the apical position of a pentagonal pyramid is well suited for such particularly large ligands; the nonbonding electron pair can occupy the [runs apical position. In contrast to the central atom in BrF; and XeFi-,['2.131 the xenon atom in XeOF; is coordinatively unsaturated. It forms intermolecular Xe-F contacts (278.4 and 298.5 pm) with two fluorine atoms of adjacent anions. This additional coordination still leaves enough space for the nonbonding lone pair. On the other hand, these intermolecular interactions are comparatively weak and have no strong structure-determining influence. We had not previously found a suitable solvent for high-resolution N M R measurements of N0'XeOF.L. NO'XeOF; dissolves in acetonitrile; in the '"F NMR spectrum at -40°C a broad signal (600 Hz) is observed at A = 141 ; this is explained by an intermolecular fluorine exchange E.xprrinirnttr1 Procedure XeOF, i i i i d NUF ( i i i the approximate ratio 1 : I ) were condensed under vacuum (staiiilcss steel v:icuum apparatus) into a perfluoroethene-propene (Teflon-FEP) tubc. which wii\ then scaled The liquid phase solidified slightly below room temperiiturc to hi-in Izirge crystals that were partly formed by sublimation a s well. Crystal sti-uctiirc an;ilysis. A suitable crystal with dimensions 0.4 x 0.4 x 0.4 mm was mounted a t IOM teiiiperature ( T = -153 'C) on an Enraf-Nonius C A D 4 diffrdcpacegn)iipP2,:n(no. 14),0 = 669.8(1).h= 551.0(1),~=1425.1(?)pm. 1) I ' = 515.9(1) pni3. Z = 4, 211max = 90'. Mo,,, 71.069 pm. (u scan. 4275 mcasured rcllcctions of which 4169 were independent and 4150 used. Lorentz pc~I~tri/iition coi-rection. Difabs absorption correction [14]. p = 68.3 m m -' , min.: may. correction 0 73'1 .lo, structure solved with the program SHELXS-86 [IS]. striicturc refiiicmcnt with SHELXL-93 [16]. 83 parameters, R, = 0.0296. wR, = 0 0806. extinction coefficient 0.01 14(9). residual electron density 1.7 c x 10" pm ' (80 pin from xenon atom). Further details ofthe crystal structure tioii mLi) be obtained from the Fachinformationszentrum Karlsruhe. ~ggcii\triii-Leopoldshafen (Germany) o n quoting the depository number