1 monoxide organometallic compounds

Organometallic Compounds. Osmium forms numerous mononuclear and polynuclear organometaUic complexes, primarily iu lower oxidation states. There are many complexes of carbon monoxide, such as [Os(CO)3] [16406-49-8], [Os(CO) H2] [22372-70-9], [Os3(CO)2 H2] [56398-24-4],... 

Organometallic Compounds. Mononuclear carbon monoxide complexes of palladium are relatively uncommon because of palladium s high labihty, tendency to be reduced, and competing migratory insertion reactions in the presence of a Pd—C bond (201). A variety of multinuclear compounds... 

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. 

Phosphorus trifluoride is a ligand that is used extensively in coordination chemistry. It substitutes readily into various metal carbonyl complexes using either thermal or photochemical techniques. As a ligand, it is unique in its similarity to carbon monoxide in lower-valent organometallic compounds. In its role as a model for CO, a number of studies are possible that cannot be done on the carbonyls themselves.1 The name normally used for PF3 in complexes is trifluorophosphine. 

Organometallic Compounds. Mononuclear carbon monoxide complexes of palladium are relatively uncommon because of palladium s high lability, tendency to be reduced, and competing migratory insertion reactions in the presence of a Pd—C bond (201). A variety of multinuclear compounds are known (202), including [Pd2Cl4(CO)2] [75991-68-3], [Pd3(P(C6H5)3)3(CO)3] [36642-60-1], and [Pd7(P(CH3)3)7(p3-CO)3(p2-CO)4] [83632-51-3]. 

A solulion of CuCl in HCI absorbs carbon monoxide, forming copperil) carbonyl chloride. Cu(CO)Cl H 0. This reaction, which is used In gas analysis, is Indicative of the ability of copper to combine with carbon monoxide. Evidence for a true carbonyl is limited to the observation that if hot carbon monoxide is passed over hot copper, a metallic mirror is produced in the hotter parts of the tube. Other organometallic compounds include Ihe very unstable methyl copper, CHiCu. phenyl copper. C<,H5Cu, and bixchlurucopper acetylene CjHrtCuCIi . 

Dative covalent bonds, or coordinate covalent bonds, are those in which electrons are shared (as in all covalent bonds), but in which both electrons involved in each bond are contributed from the same atom. Such bonds occur in organometallic compounds of transition metals having vacant d orbitals. It is beyond the scope of this book to discuss such bonding in detail the reader needing additional information should refer to works on organometallic compounds.12 The most common organometallic compounds that have dative covalent bonds are carbonyl compounds, which are formed from a transition metal and carbon monoxide, where the metal is usually in the -1, 0, or +1 oxidation state. In these compounds the carbon atom on the carbon monoxide acts as an electron-pair donor ... 

The synthesis of numerous organometallic compounds containing covalent metal-metal bonds has been achieved in a variety of ways. The majority of such compounds contain silicon, germanium, or tin bonded to a transition metal the latter frequently contains carbon monoxide among its ligands. The six principal methods of synthesis, with an example of each, are as follows ... 

The most important complexes involving carbon-containing ligands in which carbon is bound to the metal are discussed separately those of carbon monoxide in Chapter 16, organometallic compounds of transition elements, and organometallic compounds of the main group elements in the corresponding chapters. 

Chromium complexes exist in a very wide range of formal oxidation states (-IV to +VI). The extremely low ones are stabilized by jr-acid ligands, notably carbon monoxide these are described in the article on organometallic compounds (see Chromium Organometallic Chemistry). The extensive coordination chemistry of Cr spans coordination numbers 3-7, but is dominated by octahedral complexes. Complexes of... 

More universal is the method of Cp determination using selective tracers such as carbon monoxide and carbon dioxide which interact only with active metal = polymer bondsUsing tagged CO and CO2 as quenching agents systematic data have been accumulated so far on the influence of the composition of catalysts (titanium chlorides with various organometallic compounds) and polymerization conditions on Cp and kp values for the polymerization of ethylene and propylene IS)... 

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