Description

Benzenesulfonic Acid, 2-Methyl-, Dihydrate is a versatile organic acid derivative, specifically the dihydrate form of 2-methylbenzenesulfonic acid (o-toluenesulfonic acid). This compound serves as a crucial strong acid catalyst and intermediate in numerous synthetic pathways, offering a stable, solid alternative to liquid mineral acids. It is essential for manufacturers in the pharmaceutical, agrochemical, polymer, and specialty chemical industries who require precise and efficient acid catalysis or sulfonation reactions.

Application

• Pharmaceutical Synthesis: Employed as a catalyst and reagent in the production of active pharmaceutical ingredients (APIs), particularly in esterification, alkylation, and protection/deprotection reactions.
• Polymer Industry: Acts as a curing catalyst for epoxy resins and phenolic resins, and as an acid catalyst in the production of various polymers and plastics.
• Agrochemical Manufacturing: Used as a key intermediate and catalyst in the synthesis of herbicides, fungicides, and other crop protection agents.
• Dye and Pigment Production: Serves as a sulfonating agent and catalyst in the manufacture of dyes, pigments, and optical brighteners.
• Electroplating Additives: Utilized in electroplating baths as a brightening agent and stabilizer for metal deposition processes.
• Chemical Research & Development: A valuable reagent in organic synthesis laboratories for developing new chemical entities and processes.
• Catalyst for Esterification: Widely used in the synthesis of plasticizers, lubricants, and fragrances via esterification reactions.

Basic Information

Item	Detail
Product Name	Benzenesulfonic Acid, 2-Methyl-, Dihydrate
CAS No.	68066-37-5
Molecular Formula	C7H10O5S
Molecular Weight	206.22 g/mol
Synonyms	2-Methylbenzenesulfonic Acid Dihydrate; o-Toluenesulfonic Acid Dihydrate; o-TsOH·2H2O; 2-Toluenesulfonic Acid Dihydrate; ortho-Toluenesulfonic Acid Dihydrate; Benzenesulfonic Acid, Methyl-, Dihydrate; TSA Dihydrate; Tosic Acid Dihydrate
EINECS	Contact for details

Quality Control

Our Benzenesulfonic Acid, 2-Methyl-, Dihydrate is produced under a strict quality management system. Each batch undergoes rigorous analytical testing to ensure it meets precise specifications for purity, identity, and physical properties. Certificates of Analysis (COA) documenting these results are available for every shipment. We adhere to cGMP principles where applicable to support our customers in regulated industries.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, and well-ventilated area at room temperature (15-25°C). This material is hygroscopic (moisture-sensitive); ensure containers are kept tightly sealed to prevent absorption of atmospheric moisture, which can affect product quality and handling properties.

Specification

Item	Specification
Appearance	White to off-white crystalline powder
Identification (IR)	Conforms to standard
Assay (Titration)	≥ 98.0 %
Water Content (KF)	16.0 - 18.0 %
Melting Point	95 - 105 °C
Heavy Metals (as Pb)	≤ 10 ppm
Sulfate Ash	≤ 0.1 %

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.