Which one of the following is NOT correctly matched ?

Options

A. `-overset(o+)NH_3`, meta director
B. `CH_3-O-underset(OCH_3)underset(|)overset(O)overset(||)P-O`, meta director
C. meta director
D. `-CH_3` , meta direction

Answer

To solve the question "Which one of the following is NOT correctly matched?" regarding the directing effects of substituents in electrophilic aromatic substitution, we will analyze each option step by step.

### Step-by-Step Solution:

1. **Understanding Directing Effects**:
- In electrophilic aromatic substitution, substituents on the aromatic ring can either direct incoming electrophiles to the ortho and para positions (ortho-para directors) or to the meta position (meta directors).
- Ortho-para directors are typically electron-donating groups, while meta directors are usually electron-withdrawing groups.

2. **Analyzing Each Option**:
- **Option 1: NH3+ (ammonium ion)**:
- NH3+ has a positive charge on nitrogen, making it an electron-withdrawing group. Therefore, it directs electrophiles to the meta position. This option is correctly matched as a metadirector.

- **Option 2: OCH3 (methoxy group)**:
- The methoxy group (OCH3) is an electron-donating group due to the lone pair on oxygen, which increases electron density at the ortho and para positions. Thus, it is an ortho-para director, not a metadirector. This option is NOT correctly matched.

- **Option 3: P=O (phosphoryl group)**:
- The phosphoryl group (P=O) is also an electron-withdrawing group due to the high electronegativity of oxygen. It directs electrophiles to the meta position, making this option correctly matched as a metadirector.

- **Option 4: CH3 (methyl group)**:
- The methyl group (CH3) is an electron-donating group through the +I effect, which increases electron density at the ortho and para positions. Therefore, it is an ortho-para director, not a metadirector. This option is also NOT correctly matched.

3. **Conclusion**:
- The options that are NOT correctly matched are **Option 2 (OCH3)** and **Option 4 (CH3)**. However, since we need to identify one, we can conclude that **Option 4 (CH3)** is the most commonly misidentified as a metadirector.

### Final Answer:
**Option 4: CH3 is NOT correctly matched.**