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What Is Tetrahydrofuran (THF) Anhydrous?
Tetrahydrofuran (THF) Anhydrous (CAS 109-99-9) is a ether solvent with the molecular formula C4H8O and molecular weight 72.11 g/mol. [001]
Physical and Chemical Properties
| Property | Value | Source |
|---|---|---|
| CAS Number | 109-99-9 | |
| Molecular Formula | C4H8O | |
| Molecular Weight | 72.11 g/mol |
How It Works
Tetrahydrofuran (THF) is a cyclic ether that functions as a moderately polar, aprotic solvent with strong Lewis basicity. The oxygen atom in the five-membered ring is sterically accessible (unlike the oxygen in 2-methyltetrahydrofuran), allowing it to coordinate effectively to metal cations (Li⁺, Mg²⁺, Zn²⁺). This coordination is the basis for THF's unique role in organometallic chemistry: it solvates and solubilizes Grignard reagents (RMgX), organolithium compounds (n-BuLi, t-BuLi), and lithium amide bases (LDA, LiHMDS) by displacing aggregation and forming monomeric or dimeric solvated species. The Schlenk equilibrium (2 RMgX ⇌ R2Mg + MgX2) is shifted in THF due to the solvent's ability to coordinate MgX2, driving the equilibrium toward the more reactive dialkylmagnesium species. For anhydrous applications, THF must be rigorously dried — the classic method is distillation from sodium metal with benzophenone as indicator (the benzophenone ketyl radical anion is deep purple when water <10 ppm). Modern alternatives include passage through activated alumina columns or storage over activated 3Å molecular sieves for at least 24 hours.
Key Applications
- Grignard & Organometallic Reactions: Anhydrous THF is the gold standard solvent for Grignard reagent formation. THF's oxygen coordinates Mg2+, solubilizing organomagnesium species. Essential for organolithium chemistry at -78C. [004]
- Borane-THF Complex & Hydroboration: BH3-THF is the standard hydroboration reagent for anti-Markovnikov hydration of alkenes. Commercially available as 1.0 M solution, stable at 0-5C. [004]
- PTMEG/Spandex Production: THF ring-opening polymerization produces polytetramethylene ether glycol (PTMEG) -- the soft segment in spandex/elastane fibers. This accounts for ~70% of global THF consumption. [005]
- Lithium Battery Research: Anhydrous THF is used as electrolyte solvent in lithium metal battery R&D for electrochemical stability window measurements. [005]
Handling and Storage
- GHS Hazard: H225: Highly flammable liquid and vapor, H319: Causes serious eye irritation, H335: May cause respiratory irritation, H336: May cause drowsiness or dizziness, H351: Suspected of causing cancer
- Signal Word: Danger
- Pictograms: GHS02, GHS05, GHS06, GHS07, GHS08
- Storage: Store at 2-8 °C or as recommended on the Certificate of Analysis. Keep container tightly closed in a cool, dry, well-ventilated area. Protect from moisture and incompatible materials (strong oxidizing agents, acids, bases). For long-term storage, keep under inert gas (N2 or Ar) if the compound is hygroscopic or oxygen-sensitive. Always consult the supplier's Safety Data Sheet (SDS) for lot-specific storage recommendations and shelf-life information.
- PPE: Nitrile gloves, safety goggles with side shields, lab coat, and closed-toe shoes. Work in a well-ventilated fume hood. Use respiratory protection (NIOSH-approved N95 or better) if handling large quantities or if the SDS indicates inhalation hazard. [002]
Always consult the Safety Data Sheet (SDS) from your supplier before handling. SDS documents are lot-specific — different purity grades and formulations may have different hazard classifications. For bulk handling, consult your institution's chemical hygiene plan and perform a job hazard analysis (JHA) before beginning work. Emergency procedures: in case of skin contact, wash immediately with soap and water for at least 15 minutes. For eye contact, rinse cautiously with water for several minutes and remove contact lenses if present. If inhaled, move to fresh air. Seek medical attention if symptoms persist.
Regulatory & Compliance
Chemical Inventories: Tetrahydrofuran (THF) Anhydrous (CAS 109-99-9) is listed on major chemical inventories including the TSCA (Toxic Substances Control Act) inventory in the United States, EINECS (European Inventory of Existing Commercial Chemical Substances) in the EU, and similar inventories in Japan (ENCS), China (IECSC), Korea (KECL), and Australia (AICS). The specific regulatory status of CAS 109-99-9 should be verified with the appropriate national authority before importing into any jurisdiction, as inventory listing status can change with regulatory updates and new chemical assessments.
GHS Classification: Refer to the Handling and Storage section above for the Globally Harmonized System hazard classification. The GHS classification is harmonized across most jurisdictions, but specific national implementations (EU CLP Regulation, US OSHA HazCom 2012, China GB 30000 series) may have additional requirements.
Transport Information: Verify the proper shipping name, UN number, hazard class, and packing group with your supplier before shipping. Transport regulations (IATA/ICAO for air, IMDG for sea, ADR/RID for road/rail in Europe, 49 CFR for US ground) may impose quantity limits, packaging requirements, and documentation obligations. Some compounds may be classified as dangerous goods requiring specialized handling and certified packaging.
Export Control: Tetrahydrofuran (THF) Anhydrous is a standard research and industrial chemical. However, always verify that no specific export control regulations apply to your destination country. Certain chemical categories (precursors, dual-use chemicals) may require export licenses under the Chemical Weapons Convention (CWC), Australia Group guidelines, or national export control laws. Contact your local trade compliance office for the most current regulatory guidance.
[004] [002]
Frequently Asked Questions
What is the CAS number of Tetrahydrofuran (THF) Anhydrous?
The CAS Registry Number is 109-99-9. Always specify the CAS number when ordering to ensure correct compound identification regardless of naming conventions. [001]
What is the molecular weight of Tetrahydrofuran (THF) Anhydrous?
The molecular weight is 72.11 g/mol based on the molecular formula C4H8O. Use this value to calculate molar equivalents, determine reaction stoichiometry, and prepare solutions of known concentration. [001]
What is Tetrahydrofuran (THF) Anhydrous used for?
Tetrahydrofuran (THF) Anhydrous is used for: Grignard & Organometallic Reactions (Anhydrous THF is the gold standard solvent for Grignard reagent formation. THF's...); Borane-THF Complex & Hydroboration (BH3-THF is the standard hydroboration reagent for anti-Markovnikov hydration of ...); PTMEG/Spandex Production (THF ring-opening polymerization produces polytetramethylene ether glycol (PTMEG)...). For detailed protocols, see the Key Applications section above. [002]
How should Tetrahydrofuran (THF) Anhydrous be stored?
Store at 2-8 °C or as recommended on the Certificate of Analysis. Keep container tightly closed in a cool, dry, well-ventilated area. Protect from moisture and incompatible materials (strong oxidizing agents, acids, bases). For long-term storage, keep under inert gas (N2 or Ar) if the compound is hygroscopic or oxygen-sensitive. Always consult the supplier's Safety Data Sheet (SDS) for lot-specific storage recommendations and shelf-life information.. Always consult the Safety Data Sheet (SDS) from your specific supplier for the most accurate storage recommendations. [002]
Where can I buy Tetrahydrofuran (THF) Anhydrous?
Tetrahydrofuran (THF) Anhydrous (CAS 109-99-9) is available from CoreyChem. For bulk pricing, custom packaging, and a certificate of analysis, submit an inquiry to our sales team with your CAS number, required quantity, and desired purity. [003]
Where to Buy
Tetrahydrofuran (THF) Anhydrous is available in the CoreyChem catalog.
[View Tetrahydrofuran (THF) Anhydrous (CAS 109-99-9) on CoreyChem →](https://careerchemical.com/product/109-99-9) [003]
To request a quote, check bulk availability, or inquire about custom packaging for Tetrahydrofuran (THF) Anhydrous, contact our sales team at [email protected] or submit an inquiry through our website. We respond to all inquiries within one business day with pricing and availability information tailored to your specific requirements.
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References & Sources
https://www.tcichemicals.com/US/en/search/?text=109-99-9
https://pubchem.ncbi.nlm.nih.gov/compound/109-99-9
https://pubchem.ncbi.nlm.nih.gov/compound/109-99-9#section=Use-and-Manufacturing
