1,3-Propanesultone丨CAS 1120-71-4

1,3-Propanesultone丨CAS 1120-71-4 is a cyclic sulfonic ester with the molecular formula C3H6O3S. It is a highly reactive lactone of 1-hydroxypropanesulfonic acid and exists as a colorless liquid or crystalline solid under standard conditions. Due to its strained ring structure, it readily undergoes ring-opening reactions, making it a valuable intermediate in both organic synthesis and industrial applications.

1. Electrolyte Additive in Lithium-ion Batteries
1,3-Propanesultone丨CAS 1120-71-4 is widely used as a film-forming additive in electrolytes for lithium-ion batteries (LIBs):
● Solid Electrolyte Interphase (SEI) formation: It decomposes at the electrode surface during the initial charge cycle to form a stable SEI layer, which protects the anode and enhances battery lifespan.
● Improved cycling stability: The SEI formed by 1,3-propanesultone contributes to lower impedance and enhanced capacity retention during repeated charge/discharge cycles.
● Thermal stability: It helps improve the thermal performance of LIBs, supporting safety and efficiency at elevated temperatures.
2. Synthesis of Zwitterionic Surfactants and Polymers
1,3-Propanesultone丨CAS 1120-71-4 is a key precursor in the synthesis of zwitterionic compounds, especially sulfobetaines, which are used in:
● Surfactants: These compounds are non-ionic and pH-stable, ideal for applications in cosmetics, detergents, and antifouling coatings.
● Biocompatible polymers: Sulfobetaine-functionalized polymers resist protein adsorption and biofouling, making them ideal for medical devices, biosensors, and drug delivery systems.
3. Pharmaceutical Intermediates
Due to its reactivity with amines and alcohols, 1,3-propanesultone is employed in the modification of active pharmaceutical ingredients (APIs) or intermediates:
● Quaternization agent: It introduces sulfonate functional groups to enhance water solubility or modify the pharmacokinetics of compounds.
● Biofunctional molecules: Useful in preparing molecules with ionic tags for bioanalytical and diagnostic purposes.
4. Ion-exchange Resin and Membrane Modification
In the field of materials science, 1,3-propanesultone is used to modify membranes and resins:
● Ion-exchange resins: Incorporation of sulfonic acid groups through 1,3-propanesultone allows the creation of cation-exchange materials.
● Fuel cell membranes: It is used to introduce sulfonic acid functionalities in polymeric membranes, improving proton conductivity.

1. High Reactivity for Functionalization
1,3-Propanesultone's strained ring structure enables efficient ring-opening reactions with various nucleophiles, allowing for rapid and selective modification of target molecules.
2. Versatile Precursor for Functional Materials
It serves as a key building block for a wide range of materials, from ionic liquids to functional monomers, supporting innovations in energy storage, coatings, and biotechnology.
3. Enhanced Electrochemical Performance in LIBs
In lithium-ion battery applications, its use helps to extend battery life, improve safety, and maintain capacity over time by contributing to a robust SEI layer.
4. Wide Industrial Applicability
Its ability to introduce sulfonate groups makes it suitable across sectors, including electronics, cosmetics, environmental engineering, and healthcare.