Polyoxometallates transition metal substitution

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

The ample field of transition metal substituted polyoxometallates (POM), which are often other precursors for peroxo derivatives in catalytic processes, will be discussed in brief. 

Goals and five limitations in conjunction with the development of selective catalytic homogeneous oxidation systems are evaluated. Systems are presented that address several of the problems or goals. One involves oxidation of alkenes by hypochlorite catalyzed by oxidatively resistant d-electron-transition-metal-substituted (TMSP) complexes. A second involves oxidation of alkenes by H2O2 catalyzed by specific TMSP complexes, and a third addresses functionalization of redox active polyoxometalate complexes with organic groups. 

A relatively recent field of study, which, will be expanded upon later, is that of transition metal substituted polyoxometallates.43 The fact that they are, in most cases, completely inorganic means that they are inherently robust to oxidative degradation, hence, offering good prospects for industrial application. 

Zhang, X. Hill, C. L. Alkene Epoxidation by p-Cyano-lV-lV-dimethylaniline IV-oxide Catalyzed by d-Electron-transition-metal-substituted Polyoxometalates. In Catalysis of Organic Reactions. Malz, R. E. J., Ed. Marcel Dekker New York, 1996 pp 445-450. 

D. G. Musaev, K. Morokuma, Y. V. Geletii, C. L. Hill, Computational modeling of di-transition-metal-substituted /-Keggin polyoxometalate anions. Structural refinement of the protonated divacant lacunary silicodecatimgstate, Inorg. Chem. 43 (2004) 7702. 

C. L. Hill, R. B. Brown Jr., Sustained epoxidation of olefins by oxygen donors catalyzed by transition metal-substituted polyoxometalates, oxidatively resistant inorganic analogs of metalloporphyrins, J. Am. Chem. Soc. 108 (1986) 536. 

In recent years, a breakthrough in this field concerned the adoptirm of totally inorganic transition metal substituted polyoxometalates (POMs) as molecular catalysts for water oxidation. 

This book has been divided into three areas chemical detection, biological detection, and decontamination. The subject matter in the chapters include cross-linked divinyl benzene-substituted methacrylate polymers (Chapter 2), porous silicon (Chapter 3), reactive glass surfaces (Chapter 4), polycarbosilanes (Chapter 5), non-aqueous, chemically cross-linked polybutadiene gels (Chapter 6), conducting polyaniline nanofibers (Chapter 7), organically doped polystyrene and polyvinyltoluene (Chapter 8), electroplated polymer cast resins (Chapter 9), self assembled monolayers (Chapter 10), amphiphilic functionalized norbomene polymers (Chapter 11), transition metal substituted polyoxometalates (POMs) (Chapter 12), cross-linked divinyl-benzamide phospholipids (Chapter 13), and silica and organo silyl polymers (Chapter 14). 

The first reported transition metal substituted polyoxometalate, able to oxidize water was the Nai4[Ru2Zn2(H20)2(ZnW9034)2] reported by... 

Maksimchuk NV, Timofeeva MN, Melgunov MS, Shmakov AN, Chesalov YA, Dybtsev DN, et al. Heterr eneous selective oxidation catalysts based on coordination polymer MIL-101 and transition metal-substituted polyoxometalates. J Catal 2008 257 315-23. 

Figure 9.3 Various transition metal-substituting polyoxometalates.

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