For professionals in the pharmaceutical sector, the procurement of chemical intermediates like (R)-Propylene Carbonate (CAS: 16606-55-6) is a meticulously managed process. This chiral molecule is a cornerstone in the synthesis of vital medications, most notably Tenofovir. Therefore, understanding the critical factors to consider when buying this compound is essential for R&D scientists, formulation chemists, and procurement managers alike. This guide outlines the key elements for sourcing this important pharmaceutical intermediate.

1. Critical Quality Parameters: Beyond Basic Purity

While standard chemical purity (typically ≥98%) is important, the paramount specification for (R)-Propylene Carbonate in pharmaceutical applications is its enantiomeric excess (e.e.). For use in chiral synthesis, especially for APIs like Tenofovir where stereochemistry dictates biological activity, an e.e. of ≥99.0% is usually required. This ensures that the desired (R)-enantiomer is overwhelmingly present, minimizing the risk of incorporating the inactive or potentially harmful (S)-enantiomer into the final drug product. Always demand a Certificate of Analysis (CoA) from your supplier that clearly states both the chemical purity and the enantiomeric excess.

2. Understanding the CAS Number and Synonyms

The CAS number 16606-55-6 uniquely identifies (R)-Propylene Carbonate. However, suppliers may list it under various synonyms such as (R)-(+)-Propylene Carbonate, (4R)-4-methyl-1,3-dioxolan-2-one, or R-PC. Familiarizing yourself with these variations can help in broader supplier searches.

3. Application-Specific Requirements: Intermediate vs. Solvent

While primarily known as an intermediate, (R)-Propylene Carbonate also functions as a polar aprotic solvent. Depending on your specific application—whether it's a direct synthetic step or used as a reaction medium—the purity requirements might subtly differ. However, for critical synthetic steps leading to APIs, the highest purity and enantiomeric excess are always recommended.

4. Supplier Reliability and Supply Chain Security

When purchasing in bulk, supplier reliability is non-negotiable. Consider:

  • Manufacturing Location: Many high-quality chiral intermediates are sourced from manufacturers in Asia, including China. Evaluate manufacturers based on their quality systems and track record.
  • Production Capacity: Ensure the supplier can meet your volume requirements consistently. Long-term supply agreements can be beneficial for critical intermediates.
  • Regulatory Acumen: While intermediates are not APIs, suppliers familiar with pharmaceutical industry expectations regarding quality and traceability are preferable.
  • Technical Support: Access to technical data, response to inquiries, and willingness to provide samples are indicators of a reputable supplier.

5. Pricing and Quotation Process

When seeking to buy (R)-Propylene Carbonate, expect pricing to vary based on purity, volume, and supplier. Always request formal quotes for bulk orders. These quotes should detail product specifications, pack sizes, lead times, and payment terms. Compare offers from multiple reputable manufacturers to ensure competitive pricing without compromising on quality.

Conclusion

Sourcing (R)-Propylene Carbonate requires a thorough understanding of its critical quality parameters, particularly enantiomeric purity. By diligently vetting suppliers, verifying specifications, and considering the application context, pharmaceutical companies can secure this vital intermediate, ensuring the efficient and compliant production of life-saving medications. For your procurement needs, look to established manufacturers and suppliers who can guarantee the high standards required in pharmaceutical R&D and manufacturing.