Organometallic oxidant

Strassner T (2007) In Meyer F, Limberg C (eds) Organometallic oxidation catalysis. Springer, Berlin/Heidelberg. Top Organomet Chem 22 125-148... 

Furthermore reactions with difluorophosphoric anhydride are of some importance (55). The easy cleavage of the P—0—P-bridge in reactions with organometallic oxides (17) and halides (18) leads to derivatives of difluorophosphoric acid in a very mild way ... 

In a comparable maimer some organometallic oxides, such as hexamethyl disiloxane 63) and -germane, react 82) ... 

Of some importance for the preparation of various dichlorophosphates are cleaving reactions of the P-O-P bridge in P2O3CI4, which quite often reacts completely with some organometallic oxides (36) 82) or suitably substituted ethers (37) 63) ... 

The alkyl complexes mentioned above are very electron rich, and thus their susceptibility to reaction with O2 is not a great surprise, though the formation of stable organometallic oxidation products may be. Somewhat more unusual is the reaction of metal(III) hahdes with O2. Relatively recent results in this area begin with the report by Morse et al. of the oxidative addition of O2 to [Cp CrBr( ji- Br)]2, see Eq. 9 [23]. 

This principle links the typical organometallic oxidation state-based view of transition metal catalysis reactions best with the radical reaction manifold. At the end a table that links the typical radical reaction types to the different metals catalyzing them is provided. Throughout the review, series of stable organic compounds or transition metal complexes are numbered by arabic numerals and small letters, while reactive intermediates or transition states are designated by arabic numerals followed by capital letters. 

W. A. Herrmann, R. W. Fischer, and W. Scherer, Polymerization of Methyltrioxorhe-nium(VII) Organometallic Oxides as Precursors for Oxide Ceramics, Adv. Mater. 4, 653-658 (1992). 

Finally, a mention should be made about the one peroxo system which will become more and more dominant the organometallic oxides of rhenium(VII). Such compounds have been found to be of outstanding catalytic activity for a number of oxygen transfer reactions with hydrogen peroxide.92 The best studied complex is methyltrioxorhenium(VII) (MTO) and its congeners. Figure 2.32 illustrates its synthesis. Epoxidation, aromatic oxidation and halide oxidation with these complexes have been studied with hydrogen peroxide and shown to be remarkably efficacious. 

Basic ionic metal oxides or hydroxides such as CaO or KOH absorb CO2 to give metallic carbonates. Many covalent organometallic oxides or alkoxides similarly undergo insertion of carbon dioxide into the metal-oxygen bond to give the corresponding metal carbonates or alkyl metal carbonates ... 

Organometallic oxides of main group and transition elements (inorganic heterocycles) 03CRV2579. 

Organometallic Oxidation Catalysis Volume Editors E. Meyer, C. Limberg Vol. 22, 2007... 

In many stoichiometric and catalytic chemical transformations using organometallics, oxidative addition is believed to be the first step which introduces and activates substrates to the metal leading to organometallic species, and reductive elimination is the last step in which the products are released. Although little is known yet about the mechanisms of these processes, the most important point is that both bond fission and formation take place by virtue of metal oxidation and reduction under mild conditions and reactive organometallic species can be formed in the reactions. A typical example of oxidative addition has been demonstrated for Vaska s complex IrCl(CO)L2 as shown in Figure 2.17. 

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