4503-99-5Relevant articles and documents
Reactions of Monocyclopentadienyl Complexes of Molybdenum and Tungsten with Derivatives of Phenols and Pentafluorobenzeneselenol
Davidson, Jack L.,Holz, Birgit,Leverd, Pascal C.,Lindsell, W. Edward,Simpson, Nigel J.
, p. 3527 - 3532 (2007/10/02)
Reactions of (cp = η5-C5H5) with thallium salts Tl(OR) (R = aryl) in tetrahydrofuran did not produce simple substitution products but afforded reduced species 2, oxidised species or the thalliu
Electrochemical behavior of tungsten(VI) aryloxides and catecholates
Beshouri, Sharon M.,Rothwell, Ian P.
, p. 1962 - 1964 (2008/10/08)
The electrochemical behavior of a number of tungsten(VI) aryloxides and catecholates has been investigated. For deep red octahedral W(OAr-Me)6 (OAr-Me = 4-methylphenoxide), two one-electron reduction waves are present in its cyclic voltammogram in THF with 0.2 M n-Bu4N+PF6- (TBAH) as a supporting electrolyte. The first wave is reversible both chemically and electrochemically while the second electron transfer is totally irreversible. In contrast, the use of chelating aryloxides gives compounds such as W(biph)3 (biph = 2,2′-biphenoxide) and W(t-Bu2cat)3 (t-Bu2cat = 3,5-di-tert-butylcatecholate), which exhibit reversibility for both the first and second electron-transfer steps. With the less bulky catecholates, 4-methyl- and 4-tert-butylcatecholate (Mecat and t-Bucat), the electrochemical data are consistent with these complexes existing as dimers in solution, W2(Mecat)6 and W2(t-Bucat)6. Reduction occurs to generate the mononuclear anions W(Mecat)3- and W(t-Bucat)3-, respectively. Although reoxidation of these anions initially produces neutral monomers, they rapidly dimerize to the thermodynamically favored dimers. Relatively stable derivatives of the tungsten(V) monoanions can be obtained with cobaltocene as reducing agent.
