2,4-Butanesultone: Properties, Applications & Safe Handling

2,4-Butanesultone is a reactive four-membered cyclic sultone that serves as a versatile sulfonating and alkylating agent in organic synthesis and as a functional additive in lithium-ion battery electrolyte research.

CAS Number

1633-83-6

Molecular Formula

C4H8O3S

Molecular Weight

136.17 g/mol

Ring System

Four-membered cyclic sultone (1,2-oxathietane 2,2-dioxide class)

Appearance

Colorless to pale yellow liquid

Key Reactivity

Ring-opening sulfonation and alkylation with nucleophiles

Primary Research Applications

Sulfonate synthesis, surface functionalization, battery electrolyte additive

Chemical Structure and Physicochemical Properties

2,4-Butanesultone (CAS 1633-83-6) is a four-membered cyclic sultone with the molecular formula C₄H₈O₃S and a molecular weight of approximately 136.17 g/mol. Its structure consists of a strained four-membered ring formed by a sulfonate ester linkage (–O–S(=O)₂–), which confers exceptional ring-strain-driven reactivity toward a wide range of nucleophiles.

Unlike its better-known six-membered analogue 1,3-propanesultone, the four-membered ring of 2,4-butanesultone is considerably more strained, resulting in a higher intrinsic reactivity. The compound typically appears as a colorless to pale yellow liquid under ambient conditions. Its electrophilic carbon adjacent to the sulfonate oxygen is readily attacked by nucleophiles such as amines, alcohols, thiols, and carbanions, leading to ring-opening and introduction of a terminal sulfonate group into the substrate.

Researchers should note that physicochemical data such as precise boiling point, density, and refractive index should be confirmed against the current certificate of analysis (CoA) supplied with each lot of Aladdin Scientific product B152088.

Research Applications

Sulfonate and Zwitterion Synthesis: The primary application of 2,4-butanesultone in synthetic chemistry is the introduction of a –(CH₂)₃SO₃^– or –(CH₂)₄SO₃^– chain (depending on ring-opening regiochemistry) onto nucleophilic substrates. Amines, for example, react readily with 2,4-butanesultone to produce sulfobetaine-type zwitterionic products, which are valuable in the preparation of detergents, chromatographic ligands, and biomimetic surfaces.

Surface and Polymer Functionalization: 2,4-Butanesultone is used to introduce anionic sulfonate groups onto polymer backbones, silica surfaces, and carbon nanomaterials. Sulfonated polymers exhibit enhanced hydrophilicity, ion-exchange capacity, and antifouling properties, making them relevant for membrane science and biomedical coating research.

Battery Electrolyte Research: Cyclic sultones, including 2,4-butanesultone, have attracted increasing interest as electrolyte additives for lithium-ion and next-generation batteries. They can participate in solid electrolyte interphase (SEI) film formation on electrode surfaces, potentially improving cycling stability and capacity retention. Research in this area is ongoing, and users are encouraged to consult the primary literature for the latest mechanistic findings.

Ion-Liquid and Ionic Compound Synthesis: The sultone serves as a quaternizing agent for the preparation of ionic liquids and surfactants bearing sulfonate head groups, which have applications in catalysis, extraction, and green chemistry.

Safe Handling, Storage, and Regulatory Considerations

Hazard Profile: 2,4-Butanesultone is a reactive electrophile and should be handled with appropriate caution. As with other strained sultones, it may be a potential alkylating agent with associated mutagenicity concerns. Users must consult the current Safety Data Sheet (SDS) before use and comply with all institutional and regulatory requirements for handling potentially genotoxic compounds.

Personal Protective Equipment (PPE): Chemical-resistant gloves (e.g., nitrile or neoprene), a laboratory coat, and eye protection should be worn at minimum. Work in a well-ventilated fume hood is strongly recommended to prevent inhalation of vapors.

Storage: Store in a tightly sealed container under cool, dry, and well-ventilated conditions, away from moisture, oxidizers, and sources of ignition. Consult the product label and SDS for specific temperature recommendations. Proper secondary containment is advised.

Waste Disposal: Dispose of waste material and contaminated items in accordance with local, national, and institutional regulations governing hazardous chemical waste. Hydrolysis by dilute aqueous base may be employed for small-scale deactivation, but confirm appropriateness with your institution's Environmental Health and Safety office.

Regulatory Status: Users in jurisdictions subject to restrictions on carcinogenic, mutagenic, or reprotoxic (CMR) substances should verify current classification and authorization requirements before purchase and use.

Purity, Specifications, and Quality Assurance

For research applications, reagent purity is critical to reproducibility. Aladdin Scientific offers 2,4-Butanesultone (SKU: B152088) with defined purity specifications verified by analytical methods such as GC or titration. Researchers should request and review the Certificate of Analysis (CoA) for each lot to confirm purity, water content, and any other application-critical parameters.

When evaluating suitability for demanding applications such as battery electrolyte formulation or asymmetric synthesis, consider sourcing material with the highest available purity grade. Trace water or acidic impurities can accelerate hydrolysis of the sultone ring, reducing reagent efficacy and potentially introducing interfering species into sensitive reactions.

Aladdin Scientific's quality control processes are designed to provide researchers with consistent, reliable material. For specific purity certificates, spectroscopic data, or bulk inquiries, contact Aladdin Scientific technical support directly.

Frequently asked questions

What is 2,4-Butanesultone used for in the laboratory?

2,4-Butanesultone is used primarily as a sulfonating and alkylating agent in organic synthesis, enabling the introduction of sulfonate groups onto nucleophilic substrates such as amines, alcohols, and polymers. It is also investigated as a functional additive in lithium-ion battery electrolyte research for its ability to participate in SEI film formation.

How does 2,4-Butanesultone differ from 1,3-propanesultone?

While both are cyclic sultones that react with nucleophiles via ring-opening, 2,4-Butanesultone contains a four-membered ring, which is more strained than the six-membered ring of 1,3-propanesultone. This increased ring strain generally results in higher reactivity. The two compounds also differ in the length and structure of the alkyl chain introduced into the substrate upon ring-opening.

What safety precautions are required when handling 2,4-Butanesultone?

Users should always consult the current SDS before handling. As a reactive electrophile with potential alkylating and mutagenic properties, 2,4-Butanesultone should be handled in a well-ventilated fume hood using appropriate PPE including chemical-resistant gloves, lab coat, and eye protection. Storage should be in a tightly sealed container under cool, dry conditions away from moisture and oxidizers.

How should 2,4-Butanesultone be stored to maintain its quality?

Store 2,4-Butanesultone in a tightly sealed container under cool, dry, and well-ventilated conditions. Moisture accelerates ring hydrolysis and degrades reagent quality, so anhydrous storage conditions are recommended. Always refer to the product label and SDS for lot-specific storage temperature requirements.

Is 2,4-Butanesultone suitable for use as a battery electrolyte additive?

2,4-Butanesultone is under active investigation by battery researchers as an electrolyte additive, particularly for its potential to form stable SEI layers on electrode surfaces in lithium-ion systems. High-purity material is generally preferred for such applications to minimize interfering side reactions. Researchers should consult the current primary literature for the most up-to-date performance data.

References

1. General organic chemistry reference for cyclic sultone ring-opening reactions. Textbook-level mechanistic knowledge.
2. Sultone chemistry and applications in synthesis: review of sultone reagents including 1,3-propanesultone and related compounds.
3. Research literature on cyclic sultone electrolyte additives in lithium-ion batteries and SEI formation mechanisms.
4. Regulatory guidance on CMR substances (carcinogenic, mutagenic, reprotoxic) in chemical handling — refer to REACH and GHS classifications.

Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.