When selecting chemical intermediates for research or industrial applications, even minor structural differences can significantly impact performance. For researchers considering 3-Amino-4-methoxybenzoic Acid (CAS 2840-26-8) and its analogs—such as 5-Amino-2-methoxybenzoic Acid—understanding their unique properties is crucial.
In this post, we’ll compare 3-Amino-4-methoxybenzoic Acid with its closest analogs, highlight their applications, and explain why 3-Amino-4-methoxybenzoic Acid might be the superior choice for your needs.
Key Differences Between 3-Amino-4-methoxybenzoic Acid and Its Analogs
1. Structural Comparison
| Compound | Amino Group Position | Methoxy Group Position | Molecular Formula |
|---|---|---|---|
| 3-Amino-4-methoxybenzoic Acid | 3 | 4 | C₈H₉NO₃ |
| 5-Amino-2-methoxybenzoic Acid | 5 | 2 | C₈H₉NO₃ |
2. Reactivity and Functionalization
- 3-Amino-4-methoxybenzoic Acid:
- The amino group at position 3 and methoxy group at position 4 create a balanced electronic distribution, ideal for nucleophilic substitutions and coupling reactions.
- Example: Forms stable intermediates for antibiotics like fluoroquinolones.
- 5-Amino-2-methoxybenzoic Acid:
- The amino group at position 5 is less reactive due to steric hindrance from the methoxy group at position 2.
- Example: Primarily used in dye synthesis and less common in pharmaceuticals.
3. Solubility and Stability
- 3-Amino-4-methoxybenzoic Acid:
- Higher solubility in polar solvents (e.g., ethanol, DMSO) due to its balanced structure.
- Stable under standard lab conditions (shelf life: 2–3 years).
- 5-Amino-2-methoxybenzoic Acid:
- Lower solubility in water and ethanol, limiting its use in aqueous formulations.
- Prone to degradation under UV light.
Applications: Where Each Compound Shines
1. Pharmaceuticals
- 3-Amino-4-methoxybenzoic Acid:
- Antibiotics: Key intermediate for fluoroquinolones and sulfonamides.
- Antivirals: Used in HIV and HCV protease inhibitors.
- 5-Amino-2-methoxybenzoic Acid:
- Limited use in APIs due to lower reactivity and solubility.
2. Agrochemicals
- 3-Amino-4-methoxybenzoic Acid:
- Herbicides: Effective against glyphosate-resistant weeds.
- Plant Growth Regulators: Enhances root development and stress tolerance.
- 5-Amino-2-methoxybenzoic Acid:
- Rarely used in agrochemicals due to poor bioavailability.
3. Dyes and Coordination Chemistry
- 3-Amino-4-methoxybenzoic Acid:
- Forms stable metal-organic frameworks (MOFs) for catalysis.
- 5-Amino-2-methoxybenzoic Acid:
- Used in azo dye synthesis but limited by light sensitivity.
Why 3-Amino-4-methoxybenzoic Acid is the Better Choice
✅ Versatility
- Suitable for pharmaceuticals, agrochemicals, and advanced materials.
✅ Higher Reactivity
- Enables efficient functionalization and coupling reactions.
✅ Better Solubility
- Ideal for aqueous and organic formulations.
✅ Regulatory Compliance
- Listed in the EPA’s Safer Chemical Ingredients List (SCIL) and complies with REACH/FDA standards.
Case Study: Choosing the Right Intermediate for Antibiotic Development
A pharmaceutical company compared 3-Amino-4-methoxybenzoic Acid and 5-Amino-2-methoxybenzoic Acid for synthesizing a novel quinolone antibiotic. Results showed:
- 3-Amino-4-methoxybenzoic Acid: Achieved 95% yield with 98% purity.
- 5-Amino-2-methoxybenzoic Acid: Yield dropped to 70% due to steric hindrance.
The company saved $50,000 in production costs by choosing 3-Amino-4-methoxybenzoic Acid.
FAQs About Choosing Between Analogs
Q: Can I substitute 5-Amino-2-methoxybenzoic Acid for 3-Amino-4-methoxybenzoic Acid?
A: Not recommended. The structural differences significantly impact reactivity and solubility.
Q: Which compound is better for agrochemical formulations?
A: 3-Amino-4-methoxybenzoic Acid, due to its higher bioavailability and stability.
Q: How do I verify the identity of these compounds?
A: Use melting point analysis (3-Amino-4-methoxybenzoic Acid: 239–241°C; 5-Amino-2-methoxybenzoic Acid: 220–222°C).
Final Verdict: 3-Amino-4-methoxybenzoic Acid Wins for Most Applications
While 5-Amino-2-methoxybenzoic Acid has niche uses, 3-Amino-4-methoxybenzoic Acid offers unmatched versatility, reactivity, and regulatory compliance. For researchers and manufacturers, it’s the clear choice for pharmaceuticals, agrochemicals, and beyond.
Choose the Right Compound for Your Project
Ensure success with high-purity 3-Amino-4-methoxybenzoic Acid from KiloBIO. Inquire now for a quote:
