Pyrophoric organometallic compound

PYROPHORIC ORGANOMETALLIC COMPOUNDS, n.o.s. 3229 48 SELF-REACTIVE LIQUID TYPE F... 

Reacts with many metals to give hydrogen, sometimes violently. With non-metals pyrophoric hydrides may result. Frequently initiates explosive reactions between other substances. Violent reactions with many non-metal and some metal halides and oxyhalides, also with many organometallic compounds. Many metal nonmetal-lides produce toxic, flammable or pyrophoric gases on contact with diprotium monoxide. 

The organometallic compounds of the heavier alkali metals are in general extremely air- and moisture-sensitive and many are highly pyrophoric. Great care is necessary in their manipulation. 

Compounds of these metals involving either a- or tt-bonds to carbon are generally much more reactive to both air and water than those of the d-block metals. Thus there is no lanthanide equivalent of ferrocene, an unreactive air- and heat-stable compound. They are often thermally stable to 100 °C or more, but are usually decomposed immediately by air (and are not infrequently pyrophoric). Within these limitations, lanthanide organometallic compounds have their own special features, often linked with the large size of these metals. 

Zinc oxide, ZnO, is a p-type semiconductor and shows piezoelectric properties which make this material useful for microsensor devices and micromachined actuators [69, 70]. The Al-doped material is used as a transparent electrode [71]. Other applications of ZnO include gas sensors [72], solar cell windows [73] and surface acoustic devices [74]. The organometallic compounds diethylzinc, ZnEt2 [75-77], and dimethylzinc, ZnMe2 [78], are frequently used as precursors for the deposition of zinc oxide. However, these reagents are highly pyrophoric and tend to react prematurely in the presence of water or oxygen. If ZnEt2 is combined with an alcohol in the reaction chamber, stable intermediates, presumably zinc alkoxides and/or alcohol adducts, are formed in the vapor-phase [79]. These compounds are more stable than dialkyl zinc rea-... 

Substances which ignite spontaneously in air are also classified as highly flammable. Well-known examples are the alkali metals, many organometallic compounds, e. g., methyl lithium, dimethyl stannous, and many silanes or very fine metal dusts, e.g., Raney nickel, reduced ferrous compounds, and aluminum, which behave pyrophorically. 

Diethyl zinc (1952) n. C4H10Z11. A volatile pyrophoric liquid organometallic compound used to catalyze polymerization reactions and to deacidify paper. 

Hexacarbonylmolybdenum was synthesized in low yields by L. Mond by the reaction of pyrophoric molybdenum with carbon monoxide. Presently, it is prepared by carbonylation of M0CI5, molybdic acid, molybdenum sulfide, and other molybdenum compounds. The following reducing agents may be employed Mg, Al, Na, Zn, Fe, Grignard reagents, aluminum organometallic compounds, etc. Sometimes such syntheses involve dry methods whereby no solvent is used. However, most commonly. 

Substances that catch fire spontaneously in air without an ignition source are called pyrophoric. These include several elements— white phosphorus, the alkali metals (group lA), and powdered forms of magnesium, calcium, cobalt, manganese, iron, zirconium, and aluminum. Also included are some organometallic compounds, such as ethyllithium (LiC2H5) and phenyllithium (LiQHj), and some metal carbonyl compounds such as iron pentacarbonyl, Fe(CO)5. Another major class of pyrophoric compounds consists of metal and metalloid hydrides, including lithium hydride, LiH ... 

ALKYLALUMINIUM DERIVATIVES, ALKYLBORANES, ALKYLHALOBORANES ALKYLHALOPHOSPHINES, ALKYLHALOSILANES, ALKYLMETALS ALKYLNON-METAL HYDRIDES, ALKYLPHOSPHINES, ALKYLSILANES ARYLMETALS, BORANES, CARBONYLMETALS, COMPLEX ACETYLIDES COMPLEX HYDRIDES, HALOACETYLENE DERIVATIVES HEXAMETHYLNITRATODIALUMINATE SALTS, METAL HYDRIDES NON-METAL HYDRIDES, ORGANOMETALLICS, PYROPHORIC ALLOYS PYROPHORIC CATALYSTS, PYROPHORIC IRON-SULFUR COMPOUNDS PYROPHORIC METALS... 

Goti, A. et al., J. Organomet. Chem., 1994, 470(1-2), C4 This half-sandwich compound is extremely pyrophoric. See other ORGANOMETALLICS... 

This compound was pyrophoric even as arelatively dilute pentane solution (Editor s Note This was a crude preparation probably containing many other organometallics). 

Although lacking 7T-bonded compounds in low oxidation states that characterize the d-block elements, the actinides have a rich organometallic chemistry. Their compounds frequently exhibit considerable thermal stability, but like the lanthanide compounds are usually intensely air- and moisture-sensitive. They are often soluble in aromatic hydrocarbons such as toluene and in ethers (e.g., THF) but are generally destroyed by water. Sometimes they are pyrophoric on exposure to air. Most of the synthetic work has been carried out with Th and U this is partly due to the ready availability of MCI4 (M = Th, U) and also because of the precautions that have to be taken in handling compounds of other metals, especially Pu and Np. 

HEXAMETHYLNITRATODLALUMINATE SALTS, METAL HYDRIDES NON-METAL HYDRIDES, ORGANOMETALLICS, PYROPHORIC ALLOYS PYROPHORIC CATALYSTS, PYROPHORIC IRON-SULFUR COMPOUNDS PYROPHORIC METALS... 

Some compounds with organometallic character are also pyrophoric. An example of such a compound is diethylethoxyaluminum ... 

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