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Product Name: Diazomethane
Chemical Formula: CH2N2
Chemical Family: Azides
Synonyms: Methylenediazine, DM
CAS Number: 334-88-3
Recommended Use: Laboratory reagent, methylation agent
Manufacturer Details: Contact information for emergency support and technical questions should be easily available on product packaging.
Hazard Class: Highly toxic, explosive, extremely flammable gas
GHS Classification: Flammable Gas (Category 1), Acute Toxicity Inhalation (Category 1), Acute Toxicity Dermal (Category 1), Explosive (Unstable Explosive)
Signal Word: Danger
Hazard Statements: Fatal if inhaled, fatal in contact with skin, forms explosive mixtures with air, may explode spontaneously, low exposure threshold for toxic symptoms
Precautionary Statements: Avoid all contact and inhalation, only experienced personnel in controlled conditions
HMIS/NFPA Ratings: Health: 4, Flammability: 4, Reactivity: 4
Substance: Diazomethane
Purity: Usually provided in solution due to instability, typical concentration in ether 2-5%
Impurities: Potential traces of ethanol, diethyl ether, and nitrosomethylurea (precursor)
Stabilizers: Not intentionally added, any stabilization results from carrier solvent
Other Composition Notes: Solutions can still rapidly decompose, vapor may escape easily from solutions.
Inhalation: Move victim to fresh air immediately, administer oxygen if breathing becomes difficult, seek emergency medical attention, do not leave victim unattended, symptoms might include headache, cough, chest constriction, shortness of breath, or convulsions
Skin Contact: Remove any contaminated clothing, rinse skin with copious amounts of water for at least 15 minutes, medical evaluation required due to high absorption and toxicity
Eye Contact: Rinse cautiously with water for no less than 15 minutes, hold eyelids apart, medical attention necessary regardless of symptoms
Ingestion: Not a typical route due to gaseous phase but if exposure occurs rinse mouth, do not induce vomiting, contact medical personnel immediately
General Advice: Initiate decontamination procedures while awaiting emergency services, always inform doctors of potential exposure to an acutely toxic, explosive gas.
Suitable Extinguishing Media: Use carbon dioxide, dry chemical powder, or sand, never water directly on Diazomethane, as it does not control an explosive event
Specific Hazards: Explosive decomposition can be triggered by heat, shock, friction, or contamination, vapor is heavier than air and may travel
Protective Equipment for Firefighters: Use full bunker gear and self-contained breathing apparatus, approach from upwind
Special Procedures: Remove all ignition sources immediately, evacuate area, avoid disturbing material, allow fire to burn under controlled conditions if possible, consider secondary chemical exposure to methyl nitrite and nitrogen oxides
Hazardous Combustion Products: Nitrogen oxides, carbon monoxide, secondary products may form depending on what Diazomethane is in contact with during fire
Personal Precautions: Only trained, properly equipped personnel permitted, full protective gear and respiratory protection mandatory, ventilate area quickly and efficiently
Environmental Precautions: Keep away from open water sources, drains, and soil, risk of harmful ecological effect exists due to high toxicity
Methods for Cleanup: Disperse the gas with forced ventilation in a certified fume hood, use absorbents for liquid solutions, approach from upwind, never use combustible materials for cleanup, avoid any action that may create friction or static
Decontamination: Wash area down with dilute acid followed by careful neutralization, then copious amounts of water, do not reuse absorbents or contaminated tools
Handling: Only handle Diazomethane in well-ventilated, dedicated fume hoods with blast shields, minimize quantities used, never use sharp-edged glassware, ensure all equipment is electrically grounded, plan and rehearse safe disposal in advance
Storage: Do not store bulk gas, always generate freshly before use, solutions must be kept cold (below 0°C), away from all incompatible substances such as acids, bases, metals, and oxidizers, use small, pressure-sealed containers fitted with pressure relief and vent lines to scrubbers, label containers clearly with hazard information
Incompatible Materials: Glass with sharp edges, rough surfaces, acids, bases, metals (especially copper, silver, and their alloys), oxidizers, porous materials
Safe Transfer Methods: Use plastic or Teflon tubing, minimize static electricity, no transfer under positive pressure unless absolutely necessary and in explosion-proof setups
Exposure Limits: No established OSHA, NIOSH or ACGIH limits, exposure must be minimized below detectable levels, real-time monitoring recommended in work area
Engineering Controls: Always work in ventilated fume hoods with blast shields, use remote-handling tools, continuous air monitoring for diazomethane concentrations beneficial
Personal Protective Equipment: Full face-shield, chemical-resistant gloves (heavy nitrile, neoprene), splash-proof laboratory coat, chemical-resistant apron, and full head and neck coverage, suitable positive-pressure respirators
Hygiene Measures: Wash exposed skin thoroughly after handling, remove contaminated clothing and dispose safely, do not eat, drink, or smoke in work area, keep work are segregated from common areas
Environmental Controls: Sufficient ventilation, emergency power-off switches for fume hoods and equipment, keeping sorbents and neutralizers ready nearby
Appearance: Yellow gas or pale yellow ethereal solution, pungent odor reminiscent of musty fruit
Boiling Point: -23°C as a gas, boils readily at room temperature
Melting Point: -130°C
Vapor Pressure: High at room temperature
Solubility: Slightly soluble in water, very soluble in diethyl ether
Density: 1.2 g/L (gas, air = 1)
Explosive Properties: Can detonate violently by heat, light, shock, or in the presence of contaminants
Odor Threshold: Not reliably detected by smell before toxic threshold reached
Molecular Weight: 42.04 g/mol
pH: Not applicable
Autoignition Temperature: Not well-characterized, assumed extremely low
Chemical Stability: Diazomethane is unstable, prone to explosive decomposition without warning, especially over time, in contact with rough surfaces, or upon heating
Conditions to Avoid: Heat, light, shock, static, contact with metals, glass surfaces with imperfections, acids, bases, and oxidizers
Hazardous Decomposition Products: Nitrogen, carbon monoxide, methyl nitrite, formaldehyde (secondary), various toxic gases may arise under fire conditions
Incompatible Materials: Metals (especially copper/silver), mineral acids, alkalis, organic materials, oxidizers, porous and rough surfaces
Polymerization: Not known to occur, but catastrophic decomposition is possible
Acute Toxicity: Diazomethane exposure can cause rapid onset of fatal symptoms, with an LC50 in rats less than 100 ppm (inhalation)
Routes of Exposure: Inhalation, dermal absorption, eye contact
Symptoms: Headache, vomiting, fatigue, cough, difficulty breathing, pulmonary edema, convulsions, death
Delayed Effects: Pulmonary edema may develop hours after exposure, even if initial symptoms resolve
Chronic Effects: Chronic exposures not well-studied due to acute danger, some evidence points to carcinogenic potential in experimental animals
IARC/OSHA Status: Occupational carcinogen based on animal data (IARC Group 2B)
Additional Notes: Symptoms may not appear immediately, strict avoidance and rapid first response needed.
Aquatic Toxicity: Highly toxic to aquatic organisms, methyl nitrite and nitrogen derivatives are persistent and hazardous in water systems
Persistence and Degradability: Diazomethane decomposes rapidly in air or water, but byproducts may linger
Bioaccumulation Potential: Not expected to bioaccumulate due to rapid breakdown, though metabolites may persist
Mobility in Soil: High volatility, spreads rapidly in soil and water after release
Other Adverse Effects: Toxic to beneficial microbes and plant life at trace concentrations, disrupts ecological balances where released accidently
Recommended Methods: Destruction best performed by slow passage through cold, dilute acid (e.g., oxalic acid solution) in a deep fume hood, trained personnel required at all times, never incinerate bulk gas or solutions directly, avoid pouring into drains
Container Disposal: Neutralize residue and solvents prior to container disposal, triple rinse and puncture containers, treat all residues as explosive hazardous waste
Regulatory Classification: Treat all waste as acute hazardous material (RCRA P-list in the US), follow all local and national hazardous waste regulations
Precautions: Keep waste under constant ventilation, label all containers and waste streams unambiguously
UN Number: UN 1162
Shipping Name: Diazomethane, stabilized, or solution in diethyl ether
Hazard Class: 2.3 (Toxic Gas), 2.1 (Flammable Gas)
Packing Group: Not used for gases, but special packaging and documentation essential
Transport Labels: Toxic Gas, Flammable Gas, Explosive (if applicable)
Special Precautions: Never transport bulk Diazomethane, only freshly prepared solutions in authorized, shatter-resistant, pressure-relief containers, accompanied by materials to neutralize accidental emissions
Regulatory Notes: Forbidden for air transport in most jurisdictions, land or sea shipment only with special permission
DOT/ADR/IATA: Extensive prohibitions and requirements, consult hazardous material authorities prior to any transport
OSHA Status: Not specifically listed, addressed as acutely toxic and reactive hazardous chemical under general duty clause, extreme care required
TSCA Status: Listed, but subject to strict reporting and handling requirements in all laboratory and industrial uses
RCRA: Diazomethane and its solutions are listed as hazardous waste
SARA Title III: Subject to emergency release reporting, implement all emergency preparedness measures
International Regulations: Covered under EU REACH Annex I/IV, controlled under GHS as Category 1 acute toxicity and explosive, national and international transport extremely restricted
Other Regulatory Information: Only approved in specialized research settings, full compliance checks required before any use, training and certification for all handlers.
