Organometallic hydrides, oxidation

Oxidative addition of transition metal-hydride and transition metal-carhon bonds to zero-valent transition metal complexes provides convenient method for preparation of homo- and heterodinuclear organometallic complexes. Oxidative addition of iron-hydride to zero-valent platinum complex giving Fe-Pt heterodinuclear complexes was demonstrated hy the reaction of HFe[Si(OMe)3](CO)3(/c -dppe) with zero-valent platinum complex such as Pt(C2H4)3 or Pt( 1,5-cod)2 giving eventually heterodinuclear ethyl or cyclooctenyl complex (Scheme 3.86) [175]. The resulting heterodinuclear structure is stahihzed hy the bridging dppe ligand and the siloxo moiety. 

The reduction of carbonyl compounds or alkylene oxides by organometallic hydrides yields alcohols of known structure in good yields. 

Nonaqueous Bases Nonaqueous Nucleophiles Organometallic Catalytic Reduction Acidic Reduction Basic or Neutral Reduction Hydride Reduction Lewis Acids Soft Acids Radical Addition Oxidizing Agents... 

The THP group, like other acetals and ketals, is inert to nucleophilic reagents and is unchanged under such conditions as hydride reduction, organometallic reactions, or base-catalyzed reactions in aqueous solution. It also protects the hydroxyl group against oxidation. 

Similar to chemical vapor deposition, reactants or precursors for chemical vapor synthesis are volatile metal-organics, carbonyls, hydrides, chlorides, etc. delivered to the hot-wall reactor as a vapor. A typical laboratory reactor consists of a precursor delivery system, a reaction zone, a particle collector, and a pumping system. Modification of the precursor delivery system and the reaction zone allows synthesis of pure oxide, doped oxide, or multi-component nanoparticles. For example, copper nanoparticles can be prepared from copper acetylacetone complexes [70], while europium doped yttiria can be obtained from their organometallic precursors [71]. 

An area of current development is the nomenclature of organometallic compounds. Organometallic compounds of Main Group elements can, to a first approximation, be considered to be derivatives of hydrides, and the methods of substitutive nomenclature can be applied. Even then, the accessibility of different oxidation states, as with phosphorus(iii) and phosphorus(v), introduces complications. Transition metal organometallic compounds are even more difficult to treat, and the development of a unified, self-consistent and accepted and applied nomenclature is not easy. Witness the different ways (k, t and italicised symbols) for denoting donor atoms in ligands. 

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