Polyoxometalates polyoxomolybdates

Polyoxoacids, defined, 41 117,118 Polyoxometalates defined,41 117,118 transition-metal-substituted, 41 224-225 Polyoxomolybdates, 41 193 Polyoxotetramelhyleneglycol, synthesis, 41 156-157... 

More recently, some other compounds containing polyoxometallates coordinated to Bi were reported by U. Kortz et al., who investigated the interactions of amino acids with polyoxomolybdates in the presence of inter alia Bi +-ions [55,56]. A series of ionic compoimds with anions of the general formula [XM06O21 (amino acid)3] (X = As , Sb , Bi ) were prepared. In case of the bismuth derivatives the amino acids HOOC(CH2) NH2 (n = 1, 2, 3) and L-HOOCCH[(CH2)4NH2]NH2 were reacted with Na2Mo04, Bi203 and KCl in an aqueous medium (Eq. 8). 

Figure 15. Crystal structure of Compound 121 illustrating the importance of hydrogen bonding between cyclopentadienyl protons and the negatively charged polyoxomolybdate anion. [Reprinted from J. Organomet. Chem.. 488. C4 (1995) P. L. Veya and J. K. Kochi, Structural and spectral characterization of novel charge transfer salts of polyoxometalates and the cationic ferrocenyl donor. Copyright 1995, with kind permission from Elsevier Science SA, Lausanne, Switzerland]...

There is a rich chemistry of heteropolyoxomolybdates and polyoxomolybdates, and it has been shown that the chemistry of these is extraordinarily versatile, which is directly related to the fact that it is very easy to reduce Mo to Mo in aqueous solution. The generation of such molybdenum blue species adds a new dimension to polyoxometalate chemistry. 

The O M Imct triplet states are involved not only in energy transfer in polyoxometallolanthanoates but also in electron transfer for the photoredox reaction of the polyoxometalates with proton and electron donors (Yamase and Ohtaka, 1994 Yamase et al., 2003,2005,2006). This enabled us to propose a photochemical design of nano-ring Mo-blues by use of Ln in a novel bottom-up approach. Following the clarification of the primary steps of the photoredox reaction, nano-rings and nano-tubes based on Mo-blues have been successfully prepared by a photo-induced self-assembly reactions in solutions containing polyoxomolybdates, proton, electron donors, and Ln +. 

Using Dye/amine/alkyl bromide, iridium-containing photoluminescent polyacrylate films have also been manufactured. Polyoxometallate (POM)/polymer hybrid materials exhibiting modified mechanical properties (polymerized EPOX/TMPTA matrix with inserted POM clusters [XIA 15]) were synthesized in a one-step process using a silicon or phosphor polyoxomolybdate/iodonium salt/silane system. 

Schaming D, Allain C, Farha R, Goldmann M, Lobstein S, Giraudeau A, Hasenknopf B, Ruhlmann L (2010) Synthesis and photocatalytic properties of mixed polyoxometalate-porphyrin copolymers obtained from Anderson-type polyoxomolybdates. Langmuir 26 5101-5109... 

Fournier M, Louis C, Che M, Chaquin P, Masure D. Polyoxometallates as models for oxide catalysts Part I. An UV-visible reflectance study of polyoxomolybdates Inflnence of polyhe-dra arrangement on the electronic transitions and comparison with supported molybdenum catalysts. J Catal. 1989 119 400. 

---