Oiganometallic compounds

Haaland, A. Oiganometallic Compounds Studied by Gas-Phase Electron Diffraction. 53, 1-23 (1974). 

Organ nth allium (TTT) derivatives can be classified into three types R3TI, I TlX, and RTLX. The trialkyl derivatives are reactive, unstable compounds, whereas the dialkyl derivatives are among the most stable and least reactive oiganometallic compounds. The monoalkyl compounds are rather unstable and often cannot be isolated. They are important intermediates in some Tl(ffl)-promoted oiganic reactions. 

Many other oiganometallic compounds also react with carbonyl groups. Lithium alkyls and aryls add to the ester carbonyl group to give either an alcohol or an olefin. Lithium dimethylcuprate has been used to prepare ketones from esters (41). Tebbe s reagent, Cp2TiCH2AlCl(CH3)2, where Cp = clyclopentadienyl, and other metal carbene complexes can convert the C=0 of esters to 0=0 (42,43). 

Nuclear Magnetic Resonance Spectra of Oiganometallic Compounds, 3, I Nucleophilic Displacement at Silicon Recent Developments and Mechanistic Implications, 20, 265... 

D. A. Shirley, The Synthesis of Ketones from Acid Halides and Oiganometallic Compounds of Magnesium, Zinc, and Cadmium, Org. React. 1954, 8, 28—58. 

Sen, A., in Applied Homogeneous Catalysis with Oiganometallic Compounds, 2nd Edition, p. 1226 Wiley, New York, 2002. 

Much faster reaction can be achieved with strong bases (/07). The chain is started by an N-acylimide which may be N-caproyl-caprolactam produced in a slow reaction from the monomer during an induction period or an N-acylamid produced by action of a cocatalyst like for example carboxylic acid chlorides or anhydrides on caprolactam. The cocatalyst action speeds up the reaction such, that fast polymerization below the melting point of the polymer becomes possible. The strong base, such as alkali metal, metal hydride, metal amid, or oiganometallic compound, activates the monomer by lactam anion formation ... 

As mentioned above, ion pairs in the gas phase may be considered as examples of coordination number I. There are a few other examples known. For instance, the aryl radical derived from the highly slerically hindered 1,3,5-triphenylbenzene, forms one-to-one2 oiganometallic compounds of the type CuC6H2(CAH3)] and AgC l I2(C6H5)3, as shown in the margin. 

Oiganometallic Compounds Studied by Gas-Phase Election Diffraction... 

Applied Homogeneous Catalysis with Oiganometallic Compounds Transition Metals for Organic Synthesis 2" Ed, Wiley-VCH Verlag, GmbH (Weinheim) Germany 2002. 

The polypropylene that was originally described by Natta contained less than 50% isotactic fractions. The remainder was atactic material. Some stereoblocks composed of isotactic and atactic polypropylenes were also formed. This type of product forms when a-olefins are polymerized in inert hydrocarbons with catalysts prepared by reducing high-valency metal compounds, like TICU, with oiganometallic compounds like A1(C2H5)3. 

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