Product Name: 2-Oxo-5-Methylthiophene
Chemical Formula: C5H4OS
CAS Number: 13679-70-4
Synonyms: 5-Methyl-2-thiophenecarboxaldehyde, 5-Methyl-2-thiophenone
Manufacturer: Not specified
Contact Information: Emergency phone and address typically listed on supplier packaging, important for emergencies such as spills and exposures
Recommended Use: Used primarily as a research chemical and intermediate for organic synthesis
Restrictions: Not intended for medical or food applications, avoid unnecessary contact and use outside of controlled environments
Classification: Irritant, harmful by inhalation, ingestion, or skin contact
GHS Label Elements: Exclamation Mark
Signal Word: Warning
Hazard Statements: Causes skin and eye irritation, possible respiratory irritant
Precautionary Statements: Avoid breathing dust, vapors or spray, use in well-ventilated areas, wash skin thoroughly after handling, wear protective gloves/eye protection
Potential Health Effects: Inhalation may cause coughing, sore throat; skin absorption could produce redness or dryness; contact with eyes might bring about watering, irritation or redness
NFPA Ratings: Health 2, Flammability 1, Reactivity 0
Chemical: 2-Oxo-5-Methylthiophene
CAS Number: 13679-70-4
Concentration: ≥98% pure (for laboratory use), impurities less than 2% typically not specified
Impurities: Any present typically considered proprietary or not hazardous at low levels; check purchase documentation for batch specifics
Inhalation: Move exposed individual to fresh air immediately, keep at rest, seek medical advice if breathing problems persist
Skin Contact: Remove any contaminated clothing, rinse skin with plenty of running water for at least 15 minutes, do not rub area, seek medical help for persistent irritation
Eye Contact: Rinse with clean water for at least 15 minutes, keep eyelids apart, avoid rubbing, get medical attention if irritation continues
Ingestion: Rinse mouth with water, do not induce vomiting, seek medical attention for lingering symptoms
Most Important Symptoms: Skin and eye irritation, headache or dizziness in case of high inhalation
Medical Advice: Symptomatic treatment, show MSDS to healthcare provider
Suitable Extinguishing Media: Use carbon dioxide, dry chemical powder, or foam; avoid water in straight streams
Specific Hazards: May emit toxic fumes such as carbon oxides, sulfur oxides under fire conditions
Firefighter Protection: Wear self-contained breathing apparatus and chemical-resistant protection, minimize exposure to smoke and chemical fumes
Special Procedures: Cool containers at risk with water spray from a safe distance, remove containers from fire area if possible without risk
Personal Precautions: Evacuate area, avoid breathing vapors or dust, ventilate area, use appropriate protective equipment including gloves and goggles
Spill Cleanup: Avoid direct contact, collect material with suitable absorbent (vermiculite, sand), sweep up avoiding dust formation, place in tightly sealed container for disposal
Environmental Precautions: Prevent entry into sewers or waterways, notify authorities in case of significant spill affecting public environments
Decontamination: Wash non-recoverable remnants with water and detergent
Handling: Wear proper PPE including gloves, goggles, and lab coat, avoid inhalation, handle in fume hood where feasible, do not eat, drink, or smoke during use, minimize dust and vapor production, keep container tightly closed when not in use
Storage: Store in cool, dry, well-ventilated area, away from sources of ignition, incompatible substances such as oxidizers; segregate from foodstuffs, acids and strong bases
Incompatibilities: Strong oxidizing agents, prolonged exposure to heat or open flame
Occupational Exposure Limits: Not officially established, minimize exposure at all times
Engineering Controls: Use chemical fume hood for all handling, provide eye-wash stations and safety showers
Personal Protection: Wear chemical-resistant gloves (nitrile or neoprene), safety goggles, lab coat or apron; use respirator if dust or vapors are likely
Hygiene Measures: Wash hands thoroughly after handling, remove contaminated clothing immediately, do not reuse until properly cleaned, avoid bringing contaminated equipment into shared spaces
Appearance: Off-white to slightly yellow crystalline powder
Odor: Sulfur-like, characteristic thiophene odor
Odor Threshold: Not determined
pH: Not available (not soluble in water)
Melting Point: 54–56°C
Boiling Point: Around 225°C
Flash Point: 91°C (closed cup)
Evaporation Rate: Not determined
Flammability: May burn but not easily ignited
Vapor Pressure: Very low at room temperature
Vapor Density: Not available
Solubility: Poorly soluble in water, soluble in organic solvents (e.g., ethanol, DMSO)
Partition Coefficient (log Kow): Not available
Auto-Ignition Temperature: Not established
Decomposition Temperature: Not specified
Viscosity: Not applicable as solid under standard conditions
Chemical Stability: Stable at room temperature away from light and moisture
Reactivity: Will react with strong oxidizers, avoid strong acids or bases
Hazardous Reactions: No hazardous polymerization expected
Decomposition Products: Carbon dioxide, carbon monoxide, sulfur oxides, and other organic fragments under intense heat or fire
Conditions to Avoid: Exposure to excess heat, direct sunlight, contact with incompatible materials
Routes of Exposure: Skin contact, ingestion, inhalation, eye contact
Acute Effects: Skin and eye irritation, respiratory irritation or discomfort
Chronic Effects: Not well-studied due to infrequent large-scale use, recommended to avoid repeated contact
Toxicity Data: LD50/LC50 values not fully characterized for this compound
Carcinogenicity: Not listed as known or suspected carcinogen by IARC, ACGIH, NTP, OSHA
Other Risks: Limited data, avoid unnecessary exposure, treat as potentially harmful
Ecotoxicity: Not thoroughly studied, minimize release to environment
Persistence/Degradability: Data unavailable; assume persistence in soil and aquatic environments
Bioaccumulative Potential: Not determined; likely low due to molecular size and structure
Mobility in Soil: Relatively low mobility due to insolubility in water
Other Adverse Effects: May be hazardous to aquatic life in significant quantities; use designated disposal protocols
Waste Disposal Methods: Dispose of via licensed chemical waste contractor in accordance with local, state, and federal environmental regulations
Container Disposal: Triple rinse, puncture, dispose as hazardous waste or return to supplier if permitted
Contaminated Packaging: Remove residues before recycling or disposal, retain hazardous labeling until clean
Do Not: Discharge to drains, surface waters, or soil
UN Number: Not classified as dangerous goods for transport
Transport Hazard Class: Not regulated as hazardous for air, sea, or land shipment in standard laboratory quantities
Packing Group: Not applicable
Special Precautions: Keep container sealed, avoid temperature extremes, package securely to prevent leaks
Shipping Name: 2-Oxo-5-Methylthiophene (if labeled for transport)
US TSCA Status: Listed or subject to research exemption
EU Regulation: Not listed under REACH SVHC, consult substance-specific guidance in the EU
Workplace Controls: Follow OSHA laboratory safety standards, maintain up-to-date safety training records
Other Regulations: Not listed as hazardous waste under RCRA, not covered under SARA Title III; regional variations may apply and should be checked with local authorities
