How many groups are ortho/para director in the electrophillic aromatic substitution?
(i) `-NH_(2) (ii) -COH (iii) -N=O (iv) -COOH`
`(v) -Et (vi) -N = NH_(2) (vii) -SO_(3)H`
(viii) `-O-underset(O)underset(||)(C)-Ome (ix)`
`-overset(O)overset(||)(C) - NH - Me`

Answer

To determine how many groups are ortho/para directors in electrophilic aromatic substitution, we need to analyze each substituent based on its ability to donate or withdraw electrons from the benzene ring. Ortho/para directing groups are typically electron-donating groups that increase the electron density at the ortho and para positions of the aromatic ring.

Let's evaluate each substituent step by step:

1. **-NH₂ (Amino Group)**:
- The nitrogen atom has a lone pair that can donate electrons to the benzene ring.
- **Conclusion**: This group is an ortho/para director.

2. **-CHO (Aldehyde Group)**:
- The carbonyl group (C=O) is electron-withdrawing due to the electronegativity of oxygen.
- **Conclusion**: This group is a meta director, not ortho/para.

3. **-N=O (Nitro Group)**:
- The nitro group is also electron-withdrawing due to the presence of the highly electronegative oxygen.
- **Conclusion**: This group is a meta director, not ortho/para.

4. **-COOH (Carboxylic Acid Group)**:
- Similar to the aldehyde, the carboxylic acid group has a carbonyl that withdraws electrons.
- **Conclusion**: This group is a meta director, not ortho/para.

5. **-Et (Ethyl Group)**:
- The ethyl group is an alkyl group that can donate electrons through hyperconjugation.
- **Conclusion**: This group is an ortho/para director.

6. **-N=NH₂ (Hydrazine Group)**:
- The nitrogen has a lone pair that can donate electrons to the benzene ring.
- **Conclusion**: This group is an ortho/para director.

7. **-SO₃H (Sulfonic Acid Group)**:
- The sulfonic acid group is electron-withdrawing due to the presence of the highly electronegative oxygen atoms.
- **Conclusion**: This group is a meta director, not ortho/para.

8. **-O=C-OCH₃ (Acetoxy Group)**:
- The carbonyl (C=O) is electron-withdrawing, but the methoxy (OCH₃) part can donate electrons.
- However, the overall effect is that it behaves as a meta director due to the carbonyl.
- **Conclusion**: This group is a meta director, not ortho/para.

9. **-O=C-NH-Me (Amide Group)**:
- The carbonyl group is electron-withdrawing, and the nitrogen does not sufficiently donate electrons to overcome this effect.
- **Conclusion**: This group is a meta director, not ortho/para.

Now, let's summarize the findings:
- Ortho/para directors: **-NH₂, -Et, -N=NH₂**
- Meta directors: **-CHO, -N=O, -COOH, -SO₃H, -O=C-OCH₃, -O=C-NH-Me**

**Total ortho/para directing groups = 3**