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Product Name: Bromocyclopentane
Chemical Formula: C5H9Br
Other Names: Cyclopentyl bromide
CAS Number: 137-43-9
Recommended Uses: Used as an intermediate in organic synthesis, especially for pharmaceuticals and agrochemicals where cyclopentyl groups play a role in molecular structure. Not meant for food, drug, or cosmetic applications. Only for laboratory research or industrial applications where containment and control measures are possible.
Manufacturer Contact: Emergency phone and manufacturer contact info must be on the container label and safety sheet provided with the shipment from your supplier.
Classification: Flammable liquid and vapor (Category 3), Acute toxicity (Category 4, oral), Skin and eye irritant (Category 2)
Signal Word: Warning
Hazard Statements: Causes skin irritation, may cause eye irritation, harmful if swallowed or inhaled, may cause drowsiness or dizziness, may form explosive mixtures with air
Precautionary Statements: Avoid breathing mist, vapors, or spray, wear protective gloves and eye protection, keep away from heat and ignition sources, use only outdoors or in a well-ventilated area, wash hands thoroughly after handling, store locked up and only allow trained personnel to access
Bromocyclopentane: 98% or higher by weight
Impurities: Unreacted cyclopentane, trace bromine compounds at less than 1% total
Molecular Weight: 149.03 g/mol
Synonyms: Same as Identification; no significant mixture ingredients
EC Number: 205-320-4
Relevant Concentration Range: All working solutions and mixtures should be considered hazardous up to 100%
Inhalation: Move to fresh air, remove victim from exposure, keep at rest, consult a physician, and if not breathing, apply artificial respiration
Skin Contact: Remove contaminated clothing and wash skin immediately with plenty of water and soap, medical attention for irritation or symptoms
Eye Contact: Rinse cautiously with water for at least 15 minutes, remove contact lenses, seek medical attention
Ingestion: Rinse mouth, do not induce vomiting, give water to dilute only if conscious, seek immediate medical advice
Most Important Symptoms: Drowsiness, headache, respiratory irritation, skin redness, or burns in severe cases
Notes for Physician: Treat symptomatically, monitor for respiratory distress or CNS depression, observe for delayed effects
Suitable Extinguishing Media: Use water fog, foam, dry chemical powder, or carbon dioxide for fire involving this substance
Unsuitable Extinguishing Techniques: Do not use direct water stream, as this can spread flammable liquid
Specific Hazards: Vapors may form explosive mixtures with air, combustion releases toxic and corrosive gases like hydrogen bromide, carbon monoxide, carbon dioxide
Protective Equipment: Firefighters need self-contained breathing apparatus and full protective clothing
Special Procedures: Cool closed containers with water spray from safe distance to prevent pressure buildup, contain contaminated run-off to prevent environmental impact, evacuate area if large quantities ignite
Personal Precautions: Evacuate all unnecessary personnel, ventilate area, use chemical goggles, gloves, and lab coat or protective overalls, keep away from ignition sources
Environmental Precautions: Prevent from entering drains, soil, or waterways, absorb spill with inert material (like sand or vermiculite), place in chemical waste container
Cleanup Methods: Collect residue with non-sparking tools, wash down site of spillage with soap and water after material pickup, do not use combustible materials like sawdust
Containment: Seal containers for proper disposal, consult authorized waste disposal company for decontamination and cleaning
Handling: Keep container tightly closed in a chemical fume hood, avoid breathing vapors, prevent contact with skin and eyes, avoid sparks, flames, and sources of static electricity, use explosion-proof equipment
Storage: Store in cool, dry, well-ventilated area away from heat and direct sunlight, segregate from strong oxidizers and acids, keep in original container or an appropriately labeled, compatible chemical container, keep away from drain access or open environment
Engineering Controls: Use in properly vented laboratory settings or chemical manufacturing areas with exhaust hoods, explosion-proof ventilation, and spill control
Personal Protective Equipment (PPE): Wear chemical-resistant gloves (nitrile or neoprene), safety goggles, lab coat, and in operations with high vapor potential, use a respirator approved for organic vapors and brominated hydrocarbons
Occupational Exposure Limits: No specific limits for bromocyclopentane, but apply best practices for similar alkyl bromides – typically 1 ppm (skin), minimize repeated or extended exposure
Monitoring: Monitor air for organic vapor concentration routinely in workplace
Appearance: Clear, colorless to pale yellow liquid
Odor: Faint sweet odor
Boiling Point: 133–135°C
Melting Point: -63°C
Flash Point: 27°C (closed cup), flammable liquid
Density: 1.286 g/cm³ at 25°C
Vapor Pressure: 13 mm Hg at 20°C
Solubility: Insoluble in water, soluble in organic solvents such as ether and ethanol
Viscosity, pH, Partition Coefficient, Auto-Ignition Temperature: Data limited, handle as for other flammable brominated hydrocarbons
Evaporation Rate: Moderate, similar to other halocycloalkanes
Chemical Stability: Stable under recommended storage conditions in tightly sealed containers
Reactivity: Reacts vigorously with strong oxidizing agents, alkali metals, and strong bases.
Hazardous Decomposition Products: Hydrogen bromide, carbon oxides on combustion or thermal breakdown.
Conditions to Avoid: High temperature, open flame, static discharge, storing near incompatible materials.
Polymerization: Not known to polymerize, but containment failure at high temperatures may release brominated byproducts.
Acute Toxicity: Harmful by ingestion, inhalation, and dermal exposure; estimated LD50 (oral, rat) ~800 mg/kg.
Skin Corrosion/Irritation: Causes skin irritation with redness and possible burns on prolonged contact.
Serious Eye Damage/Irritation: Irritating to eyes; may cause temporary injury.
Respiratory Sensitization: May cause respiratory irritation or cough.
Repeated/Dose Toxicity: Chronic exposure may affect the liver, kidneys, or CNS.
Carcinogenicity/Mutagenicity/Reproductive Toxicity: No conclusive evidence for carcinogenicity or mutagenicity; handle with caution as for similar alkyl halides.
Aquatic Toxicity: May be toxic to aquatic organisms, possible long-term effects in aquatic environments.
Persistence/Degradability: Not readily biodegradable, may persist in soil and water if released.
Bioaccumulative Potential: Moderate bioaccumulation in aquatic species predicted.
Mobility in Soil: Potential for limited mobility due to low water solubility.
Other Adverse Effects: Avoid release into environments to prevent disruption of aquatic habitats.
Waste Treatment Methods: Dispose of as hazardous waste in accordance with local, regional, and national regulations, incinerate in approved facility with scrubber for halogen acids.
Container Disposal: Triple rinse containers, puncture, and send to licensed recycler, do not allow to reach surface water, sewers, or soil.
Recommendation: Always work with authorized chemical waste handlers for bulk quantities, label waste containers clearly, document all waste streams.
UN Number: 2735
Proper Shipping Name: Bromocyclopentane, Environmentally Hazardous Substance, Liquid, flammable
Transport Hazard Class: 3 (Flammable liquid); Subsidiary hazard: 6.1 (Toxic)
Packing Group: III
Label Required: Flammable liquid and toxic
Special Transport Precautions: Keep tightly sealed, upright, secured away from incompatible substances during transport; avoid shock, physical damage; emergency procedure guidelines supplied with transport documentation.
Inventory Listings: Listed in European EINECS, US TSCA, and similar national inventories under C5H9Br.
Control Regulations: Subject to workplace chemical safety laws, hazard labeling laws, and reporting requirements (OSHA, REACH, GHS compliant).
Chemical Safety Assessment: Safety assessment recommended before large-scale use according to local regulations.
Other Regulations: Environmental release and disposal tightly controlled in line with hazardous organic chemical handling protocols, employee training and documentation legally required for registered use.
