The compounds which contain at least one direct metal to carbon covalent bond are known as organometallic compounds many of these are thermodynamically unstable and are pyrophoric. The meta may belongs to main group, transition metal, f group metal or a metalloid i.e. selenium, boron, arsenic, silicon, antimony, germanium, and tellurium and the carbon moiety may be alkyl, alkene, alkyne, carbonyl, cyclic, heterocyclic or aromatic.1
In 1827, the discovery of Zeise’s salt, K[Pt(C2H4)Cl3], and in 1849 the preparation of metal alkyls by Edward Frankland give origin about the preparation of organometallics which is …show more content…
These have different chemical properties.
All organometallic compounds are thermodynamically unstable but some kinetically stable due to high activation energy.
The formation of M-Rn compounds becomes more endothermic down the group because the strength of M-C bonds decreases down a group.
In the presence of ether solvent many main group organometallic compounds form bridged compounds in which alkyl is bridging between metal atoms.7
Organometallic compounds of transition metals:
During 1950s the proper study of organo derivatives of transition metals begin whereas the non- transition metal organo derivatives has been studied for more than hundred years before that of transition metals. The structure of organometallic compound of transition metals looks very similar to the coordination compounds in physical and chemical properties but in actual these are much more organic as compared to coordination compounds. Some major differences in properties are:
Properties of typical coordination compounds Properties of typical organometallic compounds
Water-soluble High-melting solids (. 250°C)
High-melting solids (>250°C) Low-melting solids, or …show more content…
Because of these orbitals transition metals can form 18e complexes by utilizing all of their valance orbitals to create molecular orbitals whereas the compounds of main group elements obey the octet rule and therefore are 8e compounds. The exception to 8 valance electrons is observed in case of the compounds in which the nd orbital energy of the far-right main group element decreases as a result of which the nuclear charge increases to such a level that these orbitals are utilize to form bonds and the compounds with more than 8e are