1-Nitropropane
Synonyms: 1-nitro-propane; nitropropane-1; n-nitropropane
CAS: 108-03-2 Formula: C₃H₇NO₂ MW: 89.09 g/mol
Chemical class: nitroalkanes (linear nitroparaffins)

Definition
A flammable, colorless to pale-yellow liquid nitroalkane with a mild characteristic odor. Used primarily as a solvent and synthetic intermediate.

Physicochemical properties (typical values)

• Appearance: clear liquid; may yellow on aging

• Density (20 °C): ~1.00–1.02 g/mL

• Boiling point: ~131–133 °C

• Melting point: ~−90 °C

• Vapor pressure (20 °C): tens of Pa (moderate volatility)

• Water solubility: low (order of g/L); miscible with many organics (alcohols, ketones, ethers, esters)

• Refractive index (20 °C): ~1.394

• Flash point (closed cup): ~38–43 °C → flammable liquid (GHS/CLP Cat. 3)

• Autoignition: ~480–500 °C

• Explosive limits in air: LEL ~2–3% v/v, UEL ~10–11% v/v (approx.)

• Stability: stable at ambient conditions; decomposes when heated, releasing NOx. In strong base can form nitronate salts (handle with care).

Manufacture
Commonly produced by vapor-phase nitration of propane, yielding a mixture of 1-nitropropane and 2-nitropropane, which are separated by fractional distillation. Alternative routes start from C₃ alcohols/alkanes with nitrating systems.

Primary uses

• Solvent for resins (vinyl, acrylic), cellulose derivatives, inks, coatings, adhesives—good solvency with moderate evaporation rate.

• Intermediate in organic synthesis: source of nitronates/Michael donors; precursor to amines, nitroalcohols, and fine chemicals.

• Reaction medium in lab condensations and nitro-Michael chemistry.

Health and safety (overview)

• Acute effects: vapor may cause eye/respiratory irritation, headache, drowsiness (solvent narcosis). Skin contact can defat/irritate; eye splashes cause marked irritation.

• Systemic: nitroalkanes at high exposure can induce methemoglobinemia (cyanosis, dyspnea). 1-Nitropropane is generally less concerning than 2-nitropropane, but precautions are still required.

• Carcinogenicity: evidence for 1-NP is limited (contrast with 2-NP, which has stronger evidence); apply precautionary handling.

• Fire/explosion: flammable; vapors form explosive mixtures with air and are heavier than air → potential travel to ignition sources.

It was considered an allergen, but in 2017 the negative opinion was somewhat downgraded:

Hartwig, A., & MAK Commission. (2002). 1‐Nitropropane [MAK Value Documentation, 2017]. The MAK‐Collection for Occupational Health and Safety: Annual Thresholds and Classifications for the Workplace, 4(1), 51-72.

Risk management (engineering & PPE)

• Ventilation: local exhaust; avoid ignition sources; bond/ground containers during transfer (static).

• PPE: chemical goggles/face shield, solvent-resistant gloves (nitrile/laminate), protective garments; respirator with organic-vapor cartridges if ventilation is inadequate.

• Hygiene: minimize skin contact; remove contaminated clothing; no eating/drinking/smoking in use areas.

Storage and transport

• Store in a flammables cabinet, cool/dry, away from oxidizers and strong bases/heat.

• Containers: compatible steel or glass, tightly closed; protect from light and moisture.

• GHS labels: flame + standard flammable/irritant statements; follow supplier SDS.

• Transport: regulated as a flammable liquid (check product UN number and modal codes ADR/IMDG/IATA).

Spills and disposal

• Small spills: absorb with inert media (e.g., vermiculite), place in sealed containers.

• Prevent releases to drains/waterways (VOC).

• Disposal: controlled incineration or licensed waste contractor; treat contaminated packaging as hazardous waste.

Environmental aspects

• VOC contributing to ground-level ozone; moderate volatility.

• Biodegradability: expected but not immediate; avoid aquatic releases (limited aquatic toxicity data; act conservatively).

Quick note: comparison with 2-nitropropane

• 2-Nitropropane has stronger evidence of toxicity/carcinogenicity; 1-NP is less implicated but not benign—apply similar exposure controls.

Regulatory (generic)

• Typical CLP/GHS: Flam. Liq. 3; Eye Irrit. / STOT SE 3 (narcotic effects)—consult the specific SDS for exact H/P phrases.

• Occupational limits: check national OEL/TLV values where applicable.

Good operating practices

• Work cool when possible; cap containers promptly.

• Avoid mixing with strong bases or nitrating agents without prior assessment.

• Maintain emergency provisions (CO₂/dry-powder extinguishers, safety shower/eyewash).

Disclaimer
Data above are indicative and do not replace the supplier’s Safety Data Sheet (SDS), which remains the authoritative source for classification, exposure limits, and risk controls.