Which of the following is/are example (s) of o-bonded organometallic compound?

Options

A. `Al_(2)(CH_(3))_(6)`
B. `Pb(CH_(3))_(4)`
C. `Zn(C_(2)H_(5))_(2)`
D. Ferrocene

Answer

To determine which of the given options are examples of sigma-bonded organometallic compounds, we need to analyze each option based on the nature of the bond between the metal and the carbon.

### Step-by-Step Solution:

1. **Understanding Sigma Bonds in Organometallic Compounds**:
- Organometallic compounds are characterized by the presence of at least one bond between a carbon atom of an organic group and a metal atom.
- A sigma (σ) bond is a type of covalent bond that is formed by the direct overlap of atomic orbitals.

2. **Analyzing Each Option**:
- **Option A: Al2(C2H5)6**:
- The compound contains aluminum (Al) and ethyl groups (C2H5).
- The bond between Al and the carbon atoms in the ethyl groups is a sigma bond.
- **Conclusion**: This is a sigma-bonded organometallic compound.

- **Option B: Zn(C2H5)2**:
- This compound has zinc (Zn) bonded to two ethyl groups (C2H5).
- The bond between Zn and the carbon atoms in the ethyl groups is also a sigma bond.
- **Conclusion**: This is a sigma-bonded organometallic compound.

- **Option C: (C5H5)2Fe (Ferrocene)**:
- Ferrocene consists of iron (Fe) sandwiched between two cyclopentadienyl (C5H5) rings.
- While there are bonds between Fe and the carbon atoms, the cyclopentadienyl rings have delocalized pi bonds.
- The bonding in ferrocene is characterized by both sigma and pi interactions, but the presence of pi bonds indicates that it is not purely sigma-bonded.
- **Conclusion**: This is not a sigma-bonded organometallic compound.

3. **Final Answer**:
- The examples of sigma-bonded organometallic compounds are **Option A (Al2(C2H5)6)** and **Option B (Zn(C2H5)2)**.
- **Option C (Ferrocene)** is not a sigma-bonded organometallic compound.

### Summary of Correct Options:
- **A and B** are sigma-bonded organometallic compounds.
- **C** is not a sigma-bonded organometallic compound.