2,5-Dimethylfuran (DMF) is an organic compound with the molecular formula C₆H₈O. It consists of a five‑membered aromatic furan ring substituted with methyl groups at the 2‑ and 5‑positions. The compound is a colorless liquid at ambient temperature, with a boiling point of approximately 92 °C and a density of about 0.95 g cm⁻³. It is relatively insoluble in water but miscible with many organic solvents.
Nomenclature and identifiers
- IUPAC name: 2,5‑dimethylfuran
- CAS Registry Number: 110‑78‑5
- Synonyms: 2,5‑DMF, dimethylfuran (note: distinct from dimethylformamide, also abbreviated DMF)
Synthesis
Industrial and laboratory synthesis of 2,5-dimethylfuran commonly involves the catalytic hydrogenation of 5‑hydroxymethyl‑2‑furfural (HMF), which itself is obtained by the acid‑catalyzed dehydration of carbohydrates such as fructose. Alternative routes include the cyclization of suitable C₆ precursors under acidic conditions.
Properties and reactivity
The compound retains the aromatic character of the furan ring, exhibiting typical electrophilic substitution reactions at the remaining unsubstituted positions. The methyl substituents increase its hydrophobicity relative to unsubstituted furan. 2,5‑Dimethylfuran is flammable and can form peroxides upon prolonged exposure to air and light, a behavior shared with other furans.
Applications
2,5-Dimethylfuran has attracted interest as a renewable biofuel and fuel additive. Its high octane rating (research octane number ≈ 108) and relatively high energy density (≈ 30 MJ L⁻¹) make it a candidate for blending with gasoline to improve combustion performance and reduce dependence on petroleum‑derived fuels. Additionally, it is used as a solvent and intermediate in the synthesis of pharmaceuticals, agrochemicals, and fine chemicals.
Safety and handling
The material is classified as a flammable liquid (Category 2). Exposure routes include inhalation, ingestion, and skin contact. Standard laboratory precautions—use of fume hoods, protective gloves, and avoidance of ignition sources—are recommended. Safety data sheets (SDS) detail specific handling, storage, and disposal procedures.