Which of the following is an organometallic compound ?

Options

A. `Ti (C_2 H_5 )_4`
B. `Ti (OC_2 H_5)`
C. `Ti (OCOCH_3)_4`
D. `Ti (OC_6 H_5)_4`.

Explanation

To determine which of the given compounds is an organometallic compound, we need to identify if there is a covalent bond between a carbon atom and a metal atom in each of the options provided.

### Step-by-Step Solution:

1. **Understanding Organometallic Compounds**:
- Organometallic compounds are defined as compounds that contain at least one bond between a carbon atom and a metal atom.

2. **Analyzing the Options**:
- **Option 1: Ti-C2H5-4**
- In this compound, titanium (Ti) is bonded to four ethyl (C2H5) groups. Here, there is a direct covalent bond between the carbon atoms of the ethyl groups and the titanium atom. Therefore, this qualifies as an organometallic compound.

- **Option 2: Ti-OC2H5-4**
- In this compound, titanium is bonded to an oxygen atom (O) which is then bonded to the ethyl group (C2H5). Since the bond between titanium and the ethyl group is through an oxygen atom, this does not qualify as an organometallic compound.

- **Option 3: Ti-OCOCH3-4**
- Here, titanium is bonded to an oxygen atom, which is further bonded to an acetyl group (COCH3). Similar to the previous option, the bond between titanium and the carbon of the acetyl group is through an oxygen atom, so this is not an organometallic compound.

- **Option 4: Ti-OC6H5-4**
- In this case, titanium is bonded to an oxygen atom, which is then bonded to a phenyl group (C6H5). Again, the bond is through oxygen, meaning this does not qualify as an organometallic compound.

3. **Conclusion**:
- After analyzing all the options, we find that only **Option 1: Ti-C2H5-4** has a direct covalent bond between carbon and titanium. Therefore, the correct answer is **Option 1**.

### Final Answer:
**The organometallic compound is Option 1: Ti-C2H5-4.**