Properties

CAS Number: 80-40-0

Molecular Formula: 𝐶9𝐻12𝑂3𝑆

Molecular Weight: 200.25 g/mol

Appearance: Colorless to pale yellow liquid

Odor: Sweet, aromatic

Solubility: Soluble in organic solvents (e.g., ethanol, ether), low water solubility

Reactivity: Acts as a potent electrophile in nucleophilic substitution reactions

Density: ~1.17 g/mL (at 20∘𝐶)

Melting Point: ~−12∘𝐶

 Synonyms

4-Methylbenzenesulfonic acid ethyl ester

Ethyl p-tosylate / Ethyl Tosylate

Ethyl para-toluenesulfonate

Ethyl toluene-4-sulfonate

p-Toluenesulfonic acid ethyl ester

Ethyl p-TS

Uses and Applications

Organic Synthesis: Primarily acts as an alkylating agent to introduce ethyl groups into various molecules.

Pharmaceutical Industry: Used as an intermediate for synthesizing pharmaceutical compounds and producing benzyl ammonium bromides.

Material Science: Employed in the manufacture of photosensitive materials.

Industrial Applications: Functions as a flexibilizer for cellulose acetate.

Chemical Intermediate: Used as a reagent in specialty chemical industries for various substitution reactions.

Handling and Hazards

Ethyl p-toluenesulfonate can cause irritation to the skin and eyes. It is also identified as a potential genotoxic impurity (alkylating agent) in pharmaceutical manufacturing.

Ethyl p-toluenesulfonate (CAS 80-40-0) is a colorless to pale yellow liquid, primarily used as an efficient ethylating agent and intermediate in organic synthesis and the pharmaceutical industry. It is a sulfonated ester (𝐶9𝐻12𝑂3𝑆) often used in the production of photosensitive materials, and as a flexibilizer for cellulose acetate.