Iron, carbonyl compounds cobalt group

Examples of carbonyl insertion reactions involving compounds of Group VIII metals are more common. The reaction of iron pentacarbonyl with the cyclopropylalkene (41) involves both carbonyl insertion and cyclopropane ring opening. Reduction of cobalt(n) to cobalt(o) in aqueous ammonia is thought to involve a carbonyl insertion stage, with... 

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 ... 

The most studied reaction involves the replacement of carbonyl groups by tertiary phosphines. This proceeds most readily in the case of cobalt derivatives, manganese compounds must usually be heated, and iron compounds require irradiation (except in the case of entry 13). 

Carbon monoxide has been found to be surprisingly reactive toward the metals in Group VIII, in both their oxidized and unoxidized states. A sizable number of compounds exist in which one or more CO molecules are attached to a metal atom through the carbon typical of these are nickel tetracarbonyl, Ni(CO)4, iron pentacarbonyl, Fe(CO) cobalt carbonyl hydride, Co(CO)4H platinum carbonyl chloride, Pt(CO)2Cl2 and more complicated molecules such as Co4(CO)i2. 

Besides the mentioned catalysts, the other transition metals were also appUed in carbonylation of nitro compounds by various groups [71-79]. Such as nickel, osmium, iron, cobalt, and molybdenum. All the expected products were produced by the carbonylation of nitro compounds. Interestingly, anilines were produced from nitroarenes in the presence of Mo(CO)e and DBU under microwave irradiation in moderate to excellent yields (Scheme 9.7). 

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