Question

The common name of ${\text{K}}\left[ {{\text{PtC}}{{\text{l}}_3}\left( {{\eta ^2}.{{\text{C}}_2}{{\text{H}}_4}} \right)} \right]$ is:
A. Potassium salt
B. Zeise’s salt
C. Complex salt
D. None of these

Answer 1

Hint: Organometallic compounds include the chemistry of compounds containing metal-carbon bonds. In many complexes, both $\sigma $ and $\pi $ bonding exist between the metal atom and carbon atom. There are different types of organometallic compounds like sandwich complexes, cluster compounds, carbide clusters, etc.

Complete step by step solution:
Organoplatinum chemistry is a chemistry of organometallic compounds containing a carbon to platinum bond and the study of platinum as a catalyst. ${{\text{C}}_2}{{\text{H}}_4}$, ethylene ligand serves as two electron donors. ${\text{K}}\left[ {{\text{PtC}}{{\text{l}}_3}\left( {{\eta ^2}.{{\text{C}}_2}{{\text{H}}_4}} \right)} \right]$ is a historically significant organoplatinum compound. It is obtained from ethylene and potassium tetrachloroplatinate.
Hapticity is a word used to describe the bonding mode of a ligand to a metal center. ${\eta ^{\text{x}}}$ values for carbon ligands where the ${\text{x}}$ value is odd usually indicate anionic carbon ligands, neutral carbon $\pi $system ligands.
In the given compound, ethylene molecules are attached through both carbon atoms to the central platinum atom. Platinum atom is attached to three chlorine atoms. Potassium ion is used to balance the charge. This compound is of historical example in organometallic chemistry. It is an example for transition metal alkene complex. Thus it is named as Zeise’s salt. It was named after William Christopher Zeise.
Thus the given compound is named as Zeise’s salt.

Hence the correct option is B.

Note: Preparation of Zeise’s salt is given below:
${\text{PtC}}{{\text{l}}_4} + {\text{C}}{{\text{H}}_3}{\text{C}}{{\text{H}}_2}{\text{OH}} \to {\text{PtC}}{{\text{l}}_2}.{{\text{C}}_2}{{\text{H}}_4}\xrightarrow{{{\text{KCl}}}}{\text{K}}\left[ {{\text{PtC}}{{\text{l}}_3}\left( {{\eta ^2}.{{\text{C}}_2}{{\text{H}}_4}} \right)} \right]$
There is no localized $\sigma $ bond between the metals and carbon. This is due to the interaction between $\pi $ electrons in the unsaturated molecule and the hybrid orbitals of metal atoms. Several such olefinic complexes have been observed by X-ray diffraction method.