ISSN:
0044-2313
Keywords:
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Description / Table of Contents:
Fluorinated Organoelements: Oxidative Liquid-Phase Direct Fluorination. X. Organyloxyfluorophosphoranes: Direct Synthesis by F2-Addition to Phosphinic-, Phosphonic-, and Phosphoric-Acid Ester(fluorides) and Thermal BehaviourThe phenoxyfluorophosphoranes (PhO)2PF2R (2a: R = CH3, 2b: R = Ph) and (PhO)3-nPFn+2 (4a: n = 0, 4b: n = 1, 4c: n = 2) were obtained in reasonable yield by direct fluorination of the corresponding organyloxy(fluoro)phosphanes for the first time. Contrary to 4c the intramolecular ligand exchange can be frozen up in 4b. The up to now unknown thermally unstable alkoxy-substituted difluorides (AlkO)3-PF2Rn (6a: Alk = CH3, R = Ph), n = 2; 6b: Alk = CH2CF3, R = Ph, n = 2; 6c: Alk = CH3, R = Ph, n = 1; 6d: Alk = CH3, n = 0) were isolated by low temperature F2-addition in pure substance, too. Their thermal decomposition (scrambling, CH3F-elimination) was cleared up for 6a as model substance and transferred to (CH3O)3PF2 6d Here the splitting of (CH3)2O under “Arbusov-conditions” is very surprising. The trigonal bipyramidal covalent structure of all organyloxyphosphoranes was confirmed by multinuclear 19F, 31P{1H}, 13C{1H}) NMR experiments.
Notes:
Die Phenoxyfluorphosphorane (PhO)2PF2R (2a: R = CH3, 2b: R = Ph und (PhO)3-nPFn+2 (4a: n = 0, 4b: n = 1, 4c: n = 2 werden in guter Ausbeute erstmals durch Direktfluorierung der korrespondierenden Organyloxy(fluor)phosphane erhalten. Im Gegensatz zu 4c läßt sich in 4b der intramolekulare Ligandenaustausch einfrieren. Die bisher nicht beschriebenen, thermolabilen alkoxy-substituierten Difluoride (AlkO)3-;nPF2Rn (6a: Alk = CH3, R = Ph, n = 2; 6b: Alk = CH2CF3, R = Ph, n = 2; 6c: Alk = CH3, R = Ph, n = 1; 6d: Alk = CH3, n = 0) lassen sich ebenfalls durch F2-Addition bei tiefer Temperatur in Reinsubstanz isolieren. Ihre thermische Zersetzung (Neuverteilung, CH3F-Eliminierung) wird an 6a als Modellsubstrat aufgeklärt und auf (CH3O)3PF2 6d übertragen, wobei die Bildung von (CH3)2O unter „Arbusov-Bedingungen“ überrascht. Die trigonal-bipyramidale Kovalenz-Struktur sämtlicher Organyloxyphosphorane wird durch kombinierte 19F-, 31P{1H}- und 13C{1H}-NMR-Untersuchungen bestätigt.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/zaac.19814770607
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