Chemical Name：Methyl Benzenesulfonate
Chemical Synonyms：Methyl Benzenesulphonate; Benzenesulfonic Acid Methyl Ester; BSM
CAS No.：80-18-2
Molecular Formula：C7H8O3S
Molecular Weight：172.2
Methyl Benzenesulfonate (CAS 80-18-2), also known as Methyl Benzenesulphonate or BSM, is a sulfonate ester widely used as a methylating agent and organic synthesis intermediate in pharmaceutical, dye, and fine chemical production. It is a colorless to light yellow liquid with assay ≥99% (GC). It serves as an effective reagent for introducing methyl groups onto nucleophilic substrates containing oxygen, nitrogen, and carbon atoms . It is also recognized as a potential genotoxic impurity in drug substances, requiring appropriate handling controls in pharmaceutical applications .
Parameter | Specification |
|---|---|
Product Name | Methyl Benzenesulfonate |
Synonyms | Methyl Benzenesulphonate; Benzenesulfonic Acid Methyl Ester; BSM |
CAS Number | 80-18-2 |
Molecular Formula | C₇H₈O₃S |
Molecular Weight | 172.2 g/mol |
Assay / Purity | ≥99% (GC) |
Appearance | Colorless to light yellow clear liquid |
Boiling Point | 269 °C (approx.) |
Density | 1.3 g/cm³ (approx.) |
Refractive Index | 1.515–1.522 |
Storage | Cool, dry, well-ventilated place; keep container tightly closed |
Organic Synthesis: Effective methylating agent for introducing methyl groups onto O-, N-, and C-nucleophiles .
Pharmaceutical Intermediates: Used in the synthesis of active pharmaceutical ingredients and fine chemicals.
Dye Industry: Raw material for the production of certain synthetic dyes .
Functional Materials: Can be used in the manufacturing of thin-cation exchanger membranes .
Hazard Classification: Classified as Acute Tox. 4 (H302, harmful if swallowed), Skin Corr./Irrit. (H314/H315), Eye Dam./Irrit. (H318/H319), and Skin Sens. (H317) depending on grade and supplier classification .
Genotoxic Impurity Alert: Methyl benzenesulfonate is recognized as a potential genotoxic impurity in drug substances. Pharmaceutical buyers should implement appropriate quality controls and risk assessments .
Handling: Use in a well-ventilated area. Wear protective gloves, eye protection, and face protection. Avoid inhalation of vapors and contact with skin and eyes.
UN Number: UN3265 (Corrosive liquid, acidic, organic, n.o.s.) .
High Purity: Assay ≥99% (GC), suitable for sensitive synthesis and pharmaceutical intermediate applications.
Consistent Quality: Batch-to-batch consistency with full COA documentation for quality tracking.
Reactive Methylating Agent: The benzenesulfonate leaving group provides good reactivity and stability for methylation reactions .
Full Documentation: COA and MSDS available upon request. SDS includes hazard classification and safe handling guidance.
Standard Packaging: 25 kg / 200 kg in drums, or customized packaging upon request.
Storage Conditions: Store in a tightly closed container in a cool, dry, well-ventilated place. Protect from moisture and heat. Keep away from strong oxidizing agents, strong acids, and strong bases .
Shelf Life: 12–24 months under proper storage conditions.