Trifluoromethanesulfonic acid
Superacid Strength: Triflic acid is classified as a superacid and ranks among the strongest acids known, which contributes to its high reactivity in various chemical reactions.
High Stability: The anhydrous form demonstrates high thermal and chemical stability, exhibiting strong resistance to both oxidation and reduction. This makes it particularly suitable for demanding fine chemical synthesis.
Versatile Applications: It serves as a key reagent and catalyst in the synthesis of diverse compounds, including pharmaceuticals, agrochemicals, and specialty polymers.
Non-Oxidizing Nature: Owing to its non-oxidizing properties, triflic acid is especially valuable in processes where oxidative side reactions must be avoided, such as in advanced pharmaceutical manufacturing.
1. Product Overview
Trifluoromethanesulfonic acid, commonly known as Triflic acid (abbreviated as TfOH), is one of the strongest known organic superacids. With the chemical formula CF₃SO₃H and CAS number 1493-13-6, this colorless, hygroscopic liquid is approximately 1000 times more acidic than sulfuric acid.
What sets Triflic acid apart is its exceptional thermal and chemical stability combined with non-oxidizing and non-sulfonating properties. Its conjugate base (triflate anion, CF₃SO₃⁻) exhibits extremely low nucleophilicity and high inertness, making TfOH the ideal catalyst for generating carbocations and facilitating electrophilic aromatic substitutionswithout undesirable side reactions.
As a "universal synthetic tool," it serves as the gold standard in modern organic synthesis, particularly when conventional acids fail due to oxidation, sulfonation, or decomposition issues.
2. Key Features
Superacidity for Superior Performance
With a Hammett acidity function (H₀ ≈ -14), TfOH provides protonating power far exceeding traditional mineral acids. In esterification, alkylation, and polymerization reactions, catalytic amounts dramatically accelerate reaction rates and improve yields, reducing overall production costs.
Exceptional Chemical Stability
TfOH resists both oxidizing and reducing environments. The triflate anion demonstrates remarkable resistance to decomposition and nucleophilic attack, ensuring process stability and product purity even under harsh reaction conditions.No Sulfonation Side Reactions
Unlike sulfuric acid or chlorosulfonic acid, TfOH catalyzes Friedel-Crafts reactions and other electrophilic substitutions without sulfonating aromatic substrates—eliminating troublesome byproducts and simplifying downstream processing.Broad Solubility Profile
Miscible with water and soluble in most polar organic solvents (DMF, DMSO, acetonitrile, alcohols), TfOH enables homogeneous catalysis across diverse synthetic systems, ensuring consistent and reproducible results.High Purity Specifications
Available in purities ranging from ≥99.0% to 99.5%, with critical impurities (water, sulfate, metals) controlled to stringent levels (water ≤0.02%, sulfate ≤50 ppm)—meeting the demanding requirements of pharmaceutical intermediates and electronic chemicals.
3. Technical Specifications with Explanations
| Parameter | Typical Value | Description & Significance |
|---|---|---|
| Molecular Weight | 150.08 g/mol | Essential for stoichiometric calculations and solution preparation. |
| Purity | ≥99.0% - 99.5% | The critical quality indicator. High purity minimizes interference in sensitive reactions—trace impurities can act as chain terminators or catalyst poisons in polymerizations. |
| Boiling Point | 162°C (760 mmHg) | Enables purification via distillation. Important consideration for high-temperature processes regarding volatility and pressure requirements. |
| Density | 1.696 g/mL (20°C) | Approximately 1.7× heavier than water—critical for accurate volume-to-mass conversions during formulation. |
| Melting Point | -40°C | Remains liquid in cold environments, facilitating storage and transfer without heating requirements. |
| Water Content | ≤0.02% (200 ppm) | Critical quality parameter. TfOH is extremely hygroscopic; moisture reduces acid strength and may hydrolyze sensitive substrates or esters. |
| Sulfate Content | ≤50 ppm | Indicates residual inorganic acid from synthesis. Low sulfate prevents unwanted sulfonation or side reactions in sensitive applications. |
| Appearance | Colorless to pale yellow liquid | Visual quality indicator; discoloration may indicate contamination or degradation. |
4. Applications
Pharmaceutical & Fine Chemical Synthesis
Strong Acid Catalyst: Deprotection agent in nucleoside, antibiotic, and steroid synthesis; cyclization catalyst in complex molecule construction
Carbohydrate Chemistry: Cleavage of glycosidic bonds for protein sequencing and oligosaccharide analysis
Friedel-Crafts Reactions: Catalyst or mixed anhydride precursor for efficient aromatic ketone synthesis
Polymer & Materials Science
Polymerization Catalyst: Ring-opening polymerization of lactones, cyclic ethers; polysiloxane modification for high-performance silicone materials
Conductive Polymers: Key component in synthesizing electronically conductive polymers for advanced materials
Energy Storage & Battery Technology
Electrolyte Systems: Component in lithium-ion battery electrolytes and fuel cell membranes, leveraging high stability and conductivity for enhanced performance
Research & Analytical Chemistry
Non-aqueous Titration: Standard solution (e.g., 0.1 M in acetic acid) for acid-base titrations in non-aqueous media
Ligand Chemistry: Triflate as an exceptional leaving group for synthesizing metal complexes with specific catalytic activities (copper triflate, yttrium triflate, etc.)
5. Product Grade Comparison
| Parameter/Grade | Industrial Grade | Reagent Grade | High-Purity Electronic Grade | Custom Solutions |
|---|---|---|---|---|
| Typical Purity | ≥98.0% | ≥99.0% | ≥99.5% | 0.1M - 1.0M (in acetic acid, acetonitrile, etc.) |
| Water (H₂O) | ≤0.10% | ≤0.05% | ≤0.02% | Specified per request |
| Sulfate (SO₄²⁻) | ≤100 ppm | ≤50 ppm | ≤20 ppm | — |
| Metal Ions | Not tested | ≤10 ppm | ≤1 ppm (each) | — |
| Appearance | Pale yellow liquid | Colorless to pale yellow | Colorless, clear | Colorless, clear |
| Primary Applications | Bulk chemical synthesis, alkylation, isomerization | Pharmaceutical intermediates, organic synthesis, catalysis | Electronics, battery electrolytes, sensitive polymerizations | Analytical titration, screening, specific reaction systems |
| Packaging | 25 kg drum, 200 kg drum | 1 kg bottle, 5 kg bottle, 25 kg drum | 25 kg drum (inert gas blanketing) | 100 ml bottle, 1 L bottle |
6. Purchasing & Selection Guide
Select by Application
Industrial Grade — Ideal for bulk chemical manufacturing where cost-effectiveness is paramount. Suitable for alkylation, isomerization, and general acid catalysis where trace impurities don't affect product quality.
Reagent Grade — Recommended for pharmaceutical development and research laboratories. Ensures reproducibility and minimizes interference from impurities in sensitive synthetic sequences.
High-Purity Electronic Grade — Essential for battery materials, conductive polymers, and electronic chemical applications. Strict control of metals and water prevents performance degradation in electronic devices.
Custom Solutions — Pre-diluted formulations for analytical chemistry, small-scale screening, or specific reaction systems requiring precise concentration control.
Packaging & Storage Considerations
TfOH is extremely hygroscopic and corrosive—select suppliers offering sealed moisture-proof packaging (fluorinated bottles, PTFE-lined caps)
Upon opening, immediately purge with inert gas and reseal tightly
Consider purchasing in smaller quantities matched to consumption rates to minimize degradation from repeated opening
Safety & Regulatory Compliance
Classified as hazardous material (UN 3265, Class 8 corrosive)
Verify facility capabilities: chemical fume hood, acid-resistant gloves, face shield, appropriate storage cabinets
Ensure compliance with local regulations for corrosive chemical handling and storage
7. Frequently Asked Questions (FAQ)
Q: What advantages does triflic acid offer over sulfuric acid?
A: Three key advantages:
Non-sulfonating — Catalyzes aromatic reactions without introducing sulfonic acid groups
Non-oxidizing — Compatible with oxidation-sensitive substrates
Thermal stability — Remains active at elevated temperatures where sulfuric acid decomposes
Q: Can triflic acid (TfOH) and triflic anhydride (Tf₂O) be used interchangeably?
A: No. TfOH is a Brønsted acid for protonation and acid catalysis. Tf₂O is a powerful dehydrating agent and electrophilic reagent for introducing triflyl groups or preparing triflate esters. They serve fundamentally different synthetic purposes.
Q: Why does my product discolor after opening? Does it affect performance?
A: Discoloration (colorless → pale yellow/amber) typically results from moisture absorption or contact with trace metals. For general catalysis, slight color change may not impact performance. For electronic applications or sensitive pharmaceutical synthesis, use freshly opened high-purity material.
Q: How should I handle and dispose of used triflic acid?
A: Never pour down drains. In a fume hood with cooling and stirring, slowly add waste to excess ice water or alkaline solution (lime water, NaOH). Neutralize completely, then dispose of the resulting salt solution according to local environmental regulations for inorganic salts.
Q: What materials are compatible with triflic acid for storage and transfer?
A: Compatible materials: PTFE, PFA, glass, certain fluoropolymers. Avoid metals (especially carbon steel, aluminum), as TfOH causes rapid corrosion. For storage, use fluorinated containers with inert gas blanketing.
8. Delivery, Certification & Service
Delivery Capabilities
Inventory Status: Common specifications (25 kg drum) available from regional warehouses
Sample Program: 1 kg samples available for qualification
Small Quantities: 1-5 kg packages for R&D, typically shipped within 24 hours
Bulk Shipments: 200 kg drums and ISO tanks for industrial volumes
Logistics: Licensed hazardous material carriers with specialized corrosive chemical handling expertise
Shipping Options: Express courier (samples/small packages), LTL freight, full truckload, ocean freight
Quality Certifications
ISO 9001:2015 certified manufacturing facilities
Certificate of Analysis (COA) provided with each batch—ensuring batch-to-batch consistency
Safety Data Sheet (SDS) available in multiple languages
Third-party testing available upon request (SGS, BV, or specified laboratory)
GMP documentation available for pharmaceutical applications upon request
Technical Support & Services
Expert Consultation: PhD-level chemists available for application support, troubleshooting, and process optimization
Custom Formulation: Tailored solutions at specified concentrations in various solvents
Custom Packaging: Fluorinated bottles, specialized container sizes, inert gas blanketing
Regulatory Support: Assistance with documentation for international shipping, customs clearance, and end-use declarations
