Which of the following organometallic compounds is and bonded?
- [Fe( 5-C5H5)2]
- K[PtCl3( 2-C2H4)]
- [Co(CO)5NH3]2+
- Fe(CH3)3
Answer
(3) [Co(CO)5NH3]2+
Solution
As per NCERT, the metal–carbon bond in metal carbonyls possesses both and character.
CO donates its lone pair on carbon into a vacant metal orbital M–C bond.
A filled metal d orbital donates electrons back into the vacant antibonding * orbital of CO M–C bond (synergic bonding).
The metal carbonyl [Co(CO)5NH3]2+ is the and bonded organometallic compound.
Fe(CH3)3 has only M–C bonds.
Answer: (3)