Which of the following species does act as an electrophile ?

Options

A. `H_2 O`
B. `CH_3 -O-CH_3`
C. `overset(*)CH_3`
D. `CH_3 NH_2`

Explanation

To determine which of the given species acts as an electrophile, we first need to understand what an electrophile is. An electrophile is a species that is electron-deficient and can accept electrons. This means that the central atom in the electrophile must have vacant orbitals to accommodate the incoming electrons.

### Step-by-Step Solution:

1. **Definition of Electrophile**:
- An electrophile is a species that is electron-loving, meaning it can accept electrons due to its electron deficiency.

2. **Characteristics of Electrophiles**:
- Electrophiles must have vacant orbitals to accept electrons.
- They are typically positively charged or neutral species with an incomplete octet.

3. **Analyzing the Given Species**:
- **Water (H2O)**:
- The central atom, oxygen, has a complete octet with no vacant orbitals. Therefore, it cannot accept electrons and is not an electrophile.
- **Dimethyl Ether (CH3OCH3)**:
- Similar to water, the oxygen atom in dimethyl ether has a complete octet and no vacant orbitals, making it not an electrophile.
- **Methyl Radical (CH3·)**:
- The methyl radical has an unpaired electron and one vacant orbital available. This allows it to accept an electron, making it an electrophile.
- **Methylamine (CH3NH2)**:
- In methylamine, both carbon and nitrogen have filled orbitals and do not have vacant orbitals to accommodate additional electrons. Therefore, it is not an electrophile.

4. **Conclusion**:
- Among the given species, only the methyl radical (CH3·) acts as an electrophile.

### Final Answer:
The species that acts as an electrophile is **Methyl Radical (CH3·)**.