HuagongsheHuagongshe Chemistry Print Report · For research reference only
Diazomethane
DIAZIRINE · azimethane · Diazomethane · azimethylene · DIAZOMETHANE IN ETHER · Methane, diazo-(8CI,9CI) · Diazomethane ISO 9001：2015 REACH
Identifiers & Physical Properties
| CAS No. | 334-88-3 |
|---|---|
| Molecular formula | CH2N2 |
| Average molar mass | 42.04 g/mol |
| Monoisotopic mass | 42.02179806 g/mol |
| SMILES | C=[N+]=[N-] |
| InChIKey | YXHKONLOYHBTNS-UHFFFAOYSA-N |
| PubChem CID | 9550 |
| ChEBI | CHEBI:73716 |
| EC No. | 206-382-7 |
| DTXSID | DTXSID0024008 |
Chemical & Physical Properties
| XLogP | 1.6 |
|---|---|
| Topological polar surface area | 2 |
| Hydrogen bond donors | 0 |
| Hydrogen bond acceptors | 1 |
| Rotatable bonds | 0 |
| Heavy atoms | 3 |
| Formal charge | 0 |
| Complexity | 25.8 |
| Chemical classes | Hazardous Air Pollutants (HAPs)Nitrogen Compounds -> Other Nitrogen CompoundsFlammable agents - 4th degree |
| SpringerMaterials Properties | Coriolis coupling |
| Pesticides | Pesticide -> EPA IRIS |
| LogP (partition coefficient) | 2.00 (estimated) |
| Odor | Musty odorMusty odor (no accepted threshold value) |
| Density | 1.45Relative density (water = 1): 1.451.45 @25 °C1.45(relative gas density)1.45 g/cm3 |
| Color/Form | Yellow gas [Note: Shipped as a liquefied compressed gas] |
| Solubility | Reacts with water (NIOSH, 2024)Soluble in ... benzene, alcoholVery soluble in ether and dioxaneDecomposes in waterSolubility in water: reaction |
| Flash point | Flammable gasNA (Gas) |
| Boiling point | -9 °F at 760 mmHg (NIOSH, 2024)-23 °C-23 °C @760 [mm Hg]bp -23° |
| Decomposition | WHEN HEATED TO DECOMPOSITION ... EMITS HIGHLY TOXIC FUMES OF /NITROGEN OXIDES./ SRP: DIAZOMETHANE DOES NOT NEED TO DECOMPOSE TO EMIT TOXIC FUMES.Copper powder causes active decomposition with the evolution of nitrogen and the formation of insoluble white flakes of polymethylene. |
| Melting point | -229 °F (NIOSH, 2024)-145 °C-145° |
| Refractive index | 1.4180 (estimate) |
| Physical state | Yellow gas |
| Specific heat capacity | Cp(gas): 1.25 J/(g·K), at 25℃ |
| Exposure limits | ACGIH:TLV-TWA 0.2 ppm (0.34 mg/m3)OSHA:PEL-TWA 0.2 ppm (0.4 mg/m3)NIOSH:REL-TWA 0.2 ppm |
| EWG's Food Scores | 5 |
| FDA UNII | 60A625P70P |
| IARC | 3 (Vol. 7, Sup 7) 1987 |
| EPA Substance Registry System | Diazomethane (334-88-3) |
| GHS pictogram | GHS08 |
| Signal word | Danger |
| GHS hazard statements | H350 |
| Hazard symbols | T |
| Risk statements (R) | 45 |
| Safety statements (S) | 53-45 |
| UN transport number | 1953 |
| Occupational exposure band (OEB) | C |
| Occupational exposure limit (OEL) | TWA: 0.2 ppm (0.4 mg/m3) |
| Autoignition temperature | 150 °Cimpure material explodes at lower temperature |
| Hazard class | 2.3 |
| Hazardous substances data | 334-88-3(Hazardous Substances Data) |
| Toxicity | LCLO inhal (cat) 175 ppm (10 min)PEL (OSHA) 0.2 ppm (0.4 mg/m3)TLV-TWA (ACGIH) 0.2 ppm (0.4 mg/m3) |
| Immediately dangerous to life or health concentration | 2 ppm |
Safety & Regulations
| GHS classification | DangerH350: May cause cancer [Danger Carcinogenicity]P203, P280, P318, P405, and P501 (click each P-code to see the statement)Not Classified |
|---|---|
| Regulatory information | Hazard Traits - CarcinogenicityHepatotoxicity and Digestive System ToxicityOcular ToxicityRespiratory ToxicityThe New Jersey Worker and Community Right to Know Act requires public and private employers to provide information about hazardous substances at their workplaces. (N.J.S.A. 34:5A-1 et. seq.) |
| DOT label | Poison Gas Flammable Gas |
| Fire hazards | Excerpt from ERG Guide 119 [Gases - Toxic - Flammable]:Extremely flammable. Many reactions may cause fire or explosion. Gives off irritating or toxic fumes (or gases) in a fire. Gas/air mixtures are explosive. |
| Health hazards | Excerpt from NIOSH Pocket Guide for Diazomethane: |
| Hazards summary | The major source of exposure to diazomethane is occupational. Diazomethane is a strong respiratory irritant. Acute (short-term) inhalation exposure of humans to diazomethane may cause irritation of the eyes, cough, wheezing, asthmatic symptoms, pulmonary edema, pneumonia, dizziness, weakness, headache, and chest pains. No information is available on the chronic (long-term), reproductive, developmental, or carcinogenic effects of diazomethane in humans. Increased incidences of lung tumors have been observed in rats and mice exposed to diazomethane by inhalation and in dermally exposed mice. EPA has not classified diazomethane with respect to its potential carcinogenicity.Toxicity in experimental animals resembles that of phosgene. [ACGIH] Possible frostbite from contact with liquid[NIOSH] A corrosive substance that can cause pulmonary edemaMay cause asthma after repeated or prolonged exposures[ICSC] |
| Reactive group | Azo, Diazo, Azido, Hydrazine, and Azide Compounds |
| EC classification | Symbol: TR: 45S: 53-45 |
| Reactivity Alerts | Explosive |
| OSHA Standards | Permissible Exposure Limit: Table Z-1 8-hr Time Weighted Avg: 0.2 ppm (0.4 mg/cu m). |
| Reactivity Profile | DIAZOMETHANE undergoes violent thermal decomposition. Above 200 °C. the vapors may explode violently if rough glass surfaces are present. Explosions at low temperatures can occur if traces of organic matter are present. [J. Phys. Chem. 35:1403(1931)]. Produces explosions with alkali metals. Reacts with copper powder and to some extent all solid surfaces to produce nitrogen and solid white polymethylene. Reacts with dimethylaminodimethylarsine and trimethyltin in ether with vigorous foaming. |
| Atmospheric standards | Listed as a hazardous air pollutant (HAP) generally known or suspected to cause serious health problems. The Clean Air Act, as amended in 1990, directs EPA to set standards requiring major sources to sharply reduce routine emissions of toxic pollutants. EPA is required to establish and phase in specific performance based standards for all air emission sources that emit one or more of the listed pollutants. Diazomethane is included on this list. |
| Chemical Dangers | May decompose explosively on shock, friction or concussion. May explode on heating at 100 °C or on contact with rough surfaces or if impurities or solids are present in the undiluted liquid or in the concentrated solutions or under high intensity lighting. Contact with alkali metals and calcium sulfate causes explosion. |
| Fire fighting | Excerpt from ERG Guide 119 [Gases - Toxic - Flammable]:Shut off supplyif not possible and no risk to surroundings, let the fire burn itself out. In other cases extinguish with powder, carbon dioxide. Combat fire from a sheltered position. |
| First aid measures | Fresh air, rest. Half-upright position. Artificial respiration may be needed. Refer immediately for medical attention.ON FROSTBITE: rinse with plenty of water, do NOT remove clothes. Refer immediately for medical attention. Wear protective gloves when administering first aid.First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention. Keep rinsing during transport for medical attention.Unlikely under occupational conditions. |
| First aid | Excerpt from NIOSH Pocket Guide for Diazomethane:(General first aid procedures) |
| Safe storage | Solutions of diazomethane should not be stored. |
| Firefighting Hazards | ... Vapors may travel long distances to ignition sources and flashback. Vapors in confined areas may explode when exposed to fire. Containers may explode in fire. ... |
| Fire fighting procedures | If material /is/ on fire or involved in /a/ fire use dry chemical, dry sand, or carbon dioxide. Do not use water on material itself. If large quantities of combustibles are involved, use water in flooding quantities as spray and fog. Use water spray to knock-down vapors. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible.Fires involving diazomethane should be fought upwind from the maximum distance possible. Diazomethane will explode in a fire. The fire area should be evacuated immediately. Keep unnecessary people awayisolate the hazard area and deny entry. Vapors may travel to a source of ignition and flash back. Vapors are an explosion and poison hazard indoors, outdoors, or in sewers. |
| Storage conditions | Diazomethane should be stored in a cool, dry, well-ventilated area in tightly sealed containers that are labeled in accordance with OSHA's Hazard Communication Standard. Containers of diazomethane should be protected from shock, heat, sparks, open flames and physical damage and should be stored separately from alkali metals, calcium sulfate, calcium chloride, boiling stones, or copper powder. Outside or detached storage is preferred. Empty containers of diazomethane should be handled appropriately.Because of its toxicity and its explosive nature, diazomethane is freshly prepared in situ and used in solution of ether or dioxane. ...... Diazomethane must be stored to avoid contact with alkali metals , such as lithium, sodium, or potassiumor drying agents such as calcium sulfate, since violent reactions occur. Safety barriers or shields should be used to protect workers from accidental explosions. ... |
| Cleanup methods | In the event of a spill or leak involving diazomethane, persons not wearing protective equipment and clothing should be restricted from contaminated areas until cleanup has been completed. The following steps should be undertaken following a spill or leak: Notify safety personnel. Remove all sources of heat and ignition. Ventilate potentially explosive atmospheres. Provide and require the use of fully-encapsulating, vapor-protective clothing and equipment for cleanup personnel. If possible without risk, stop flow of gas. If source of leak is a cylinder and cannot be stopped in place, remove the leaking cylinder to a safe place in the open air, and repair leak or allow cylinder to empty. If the leak is in the liquid form, allow diazomethane to evaporate.Decompose chemically with ceric ammonium nitrate under constant agitation and cooling. |
| Nonfire spill response | Excerpt from ERG Guide 119 [Gases - Toxic - Flammable]: |
| Disposal methods | SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination. Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air qualitypotential migration in soil or watereffects on animal and plant lifeand conformance with environmental and public health regulations.SRP: Wastewater from contaminant suppression, cleaning of protective clothing/equipment, or contaminated sites should be contained and evaluated for subject chemical or decomposition product concentrations. Concentrations shall be lower than applicable environmental discharge or disposal criteria. Alternatively, pretreatment and/or discharge to a permitted wastewater treatment facility is acceptable only after review by the governing authority and assurance that "pass through" violations will not occur. Due consideration shall be given to remediation worker exposure (inhalation, dermal and ingestion) as well as fate during treatment, transfer and disposal. If it is not practicable to manage the chemical in this fashion, it must be evaluated in accordance with EPA 40 CFR Part 261, specifically Subpart B, in order to determine the appropriate local, state and federal requirements for disposal.DIAZOMETHANE MAY BE DISPOSED OF BY BURNING AT SAFE LOCATION OR IN SUITABLE COMBUSTION CHAMBER EQUIPPED WITH AN APPROPRIATE EFFLUENT GAS CLEANING DEVICE. |
| Spillage disposal | Evacuate danger area! Consult an expert! Ventilation. Personal protection: complete protective clothing including self-contained breathing apparatus. |
| Preventive Measures | EXPLOSIVE (USE SAFETY SCREEN), INSIDIOUS POISON (WELL-VENTILATED HOOD IS ABSOLUTELY NECESSARY), AVOID VAPOR.If material /is/ not on fire and not involved in /a/ fire, keep sparks, flames, and other sources of ignition away. Keep material out of water sources and sewers. Build dikes to contain flow as necessary. Use water spray to knock-down vapors. Do not use water on material itself. Neutralize spilled material with crushed limestone, soda ash, or lime.Avoid breathing vapors. Keep upwind. Avoid bodily contact with the material. Do not handle broken packages unless wearing appropriate personal protective equipment. Wash away any material which may have contacted the body with copious amounts of water or soap and water. If contact with the material anticipated, wear appropriate chemical protective clothing.If diazomethane contacts the skin, workers should flush the affected areas immediately with plenty of water, followed by washing with soap and water. Clothing contaminated with diazomethane should be removed immediately, and provisions should be made for the safe removal of the chemical from the clothing. Persons laundering the clothes should be informed of the hazardous properties of diazomethane, particularly its potential for causing severe irritation.For more Preventive Measures (Complete) data for DIAZOMETHANE (9 total), please visit the HSDB record page. |
| Interactions | NO VANCOMYCIN WAS ADSORBED TO CELL WALLS /OF BACILLUS SUBTILIS W23/ THAT HAD BEEN ESTERIFIED BY TREATMENT WITH DIAZOMETHANE. |
| Target organs | Eyes, respiratory system |
| Environmental fate | TERRESTRIAL FATE: Since diazomethane is a gas and undergoes rapid hydrolysis with water, volatilization from soil is not relevant. Similarly, adsorption to soil and biodegradation are not expected due to the rapid rate of decomposition under environmental conditions. (SRC)AQUATIC FATE: Since diazomethane is a gas and undergoes rapid hydrolysis with water, volatilization from water is not relevant. Similarly, hydrolysis, adsorption to sediments, bioconcentration, and biodegradation are not expected due to the rapid rate of decomposition under environmental conditions. (SRC)ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), diazomethane, which has an estimated vapor pressure of 3.94X10+3 mm Hg at 25 °C(SRC), determined from a fragment constant method(2), is expected to exist solely as a gas. Gas-phase diazomethane will undergo rapid hydrolysis with atmospheric water vapor but may also be degraded by reaction with photochemically-produced hydroxyl radicals at a much slower rate(SRC)the half-life for this reaction in air is estimated to be 16 days(SRC), calculated from its rate constant of 9.34X10-13 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). The rate constant for the gas-phase reaction of diazomethane with ozone was 3.3X10-17 cu cm/molecule-sec(4). Diazomethane does not contain chromophores that absorb at wavelengths >290 nm(5), and therefore is not expected to be susceptible to direct photolysis by sunlight(SRC). |
| Adverse effects | Dermatotoxin - Skin burns. |
| Exposure routes | The substance can be absorbed into the body by inhalation.inhalation, skin and/or eye contact (liquid) |
| Signs and Symptoms | Sore throat. Headache. Laboured breathing. Shortness of breath. Nausea. Vomiting. Symptoms may be delayed.Redness. Pain. Skin burns. Burning sensation. ON CONTACT WITH LIQUID: FROSTBITE.Burning sensation. Redness. Pain. Burns. Loss of vision. ON CONTACT WITH LIQUID: FROSTBITE.irritation eyescough, short breathheadache, lassitude (weakness, exhaustion)flush skin, feverchest pain, pulmonary edema, pneumonitisasthmaliquid: frostbite |
| EPA IRIS Information | Diazomethane |
| Medical Surveillance | Medical Screening: Workers who may be exposed to chemical hazards should be monitored in a systematic program of medical surveillance that is intended to prevent occupational injury and disease. The program should include education of employers and workers about work-related hazards, early detection of adverse health effects, and referral of workers for diagnosis and treatment. The occurrence of disease or other work-related adverse health effects should prompt immediate evaluation of primary preventive measures (e.g., industrial hygiene monitoring, engineering controls, and personal protective equipment). A medical surveillance program is intended to supplement, not replace, such measures. To detect and control work-related health effects, medical evaluations should be performed (1) before job placement, (2) periodically during the term of employment, and (3) at the time of job transfer or termination.Pre-placement medical evaluation: Before a worker is placed in a job with a potential for exposure to diazomethane, a licensed health care professional should evaluate and document the worker's baseline health status with thorough medical, environmental, and occupational histories, a physical examination, and physiologic and laboratory tests appropriate for the anticipated occupational risks. These should concentrate on the function and integrity of the eyes, skin, and respiratory tract. Medical surveillance for respiratory disease should be conducted using the principles and methods recommended by the American Thoracic Society. A pre-placement medical evaluation is recommended to assess medical conditions that may be aggravated or may result in increased risk when a worker is exposed to diazomethane at or below the prescribed exposure limit. The health care professional should consider the probable frequency, intensity, and duration of exposure as well as the nature and degree of any applicable medical condition. Such conditions (which should not be regarded as absolute contraindications to job placement) include a history and other findings consistent with diseases of the eyes, skin, or respiratory tract.Periodic medical evaluations: Occupational health interviews and physical examinations should be performed at regular intervals during the employment period, as mandated by any applicable Federal, State, or local standard. Where no standard exists and the hazard is minimal, evaluations should be conducted every 3 to 5 years or as frequently as recommended by an experienced occupational health physician. Additional examinations may be necessary if a worker develops symptoms attributable to diazomethane exposure. The interviews, examinations, and medical screening tests should focus on identifying the adverse effects of diazomethane on the eyes, skin, or respiratory tract. Current health status should be compared with the baseline health status of the individual worker or with expected values for a suitable reference population.Termination medical evaluations: The medical, environmental, and occupational history interviews, the physical examination, and selected physiologic or laboratory tests that were conducted at the time of placement should be repeated at the time of job transfer or termination to determine the worker's medical status at the end of his or her employment. Any changes in the worker's health status should be compared with those expected for a suitable reference population.Biological monitoring: Biological monitoring involves sampling and analyzing body tissues or fluids to provide an index of exposure to a toxic substance or metabolite. No biological monitoring test acceptable for routine use has yet been developed for diazomethane. |
| Soil Adsorption/Mobility | Diazomethane is a gas and undergoes rapid hydrolysis with watertherefore, adsorption is not expected to be an important environmental fate process. (SRC) |
| Human Toxicity Excerpts | /SIGNS AND SYMPTOMS/ ON SKIN ... /IT/ CAUSES SEVERE, DELAYED INFLAMMATORY REACTION./SIGNS AND SYMPTOMS/ ... Inhalation can cause severe lung damage with symptoms of coughing, chest pain, shortness of breath, fever and fatigue. Exposure to the gas or liquid can cause severe skin burns and eye damage. Contact with liquid can cause frostbite./SIGNS AND SYMPTOMS/ The toxic effects of diazomethane advance insidiously. Diazomethane exposure has caused irritation of the eyes, dizziness, denudation of mucus membranes, and sensitization in laboratory workers. Chest pain, fever, and sever asthmatic attacks have been reported/SIGNS AND SYMPTOMS/ Inhalation of diazomethane by man, depending on degree of exposure caused chest pains, asthmatic symptoms, cough and fever, fulminating pneumonia, moderate cyanosis, shock and death.For more Human Toxicity Excerpts (Complete) data for DIAZOMETHANE (12 total), please visit the HSDB record page. |
| Artificial Pollution Sources | Diazomethane's production and use as a powerful methylating agent for acidic compounds such as carboxylic acids, phenols, enols(1) used in synthetic organic transformations may result in its release to the environment through various waste streams(SRC). |
| Environmental Biodegradation | Diazomethane is a gas and reacts rapidly with watertherefore biodegradation is not expected to be an important environmental fate process. (SRC) |
| CERCLA reportable quantities | Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 100 lb or 45.4 kg. The toll free number of the NRC is (800) 424-8802. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV.D.3.b). |
| Occupational exposure band (OEB) | C |
| Occupational exposure limit (OEL) | TWA: 0.2 ppm (0.4 mg/m3) |
| Immediately dangerous to life or health concentration | 2 ppm |
| UN transport number | 1953 |
| Toxicity | LCLO inhal (cat) 175 ppm (10 min)PEL (OSHA) 0.2 ppm (0.4 mg/m3)TLV-TWA (ACGIH) 0.2 ppm (0.4 mg/m3) |
| Risk statements (R) | 45 |
| Signal word | Danger |
| GHS pictogram | GHS08 |
| Hazard symbols | T |
| Safety statements (S) | 53-45 |
| Hazard class | 2.3 |
| GHS hazard statements | H350 |
| Autoignition temperature | 150 °Cimpure material explodes at lower temperature |
| Hazardous substances data | 334-88-3(Hazardous Substances Data) |
Applications & Uses
Description
At room temperature, diazomethane (CH2N2) is a toxic yellow gas which can cause significant irritation upon inhalation. Solutions that contain concentrated diazomethane are highly toxic, and they can result in explosions. When heated, Diazomethane emits toxic fumes made of nitrogen oxides; the toxic fumes are also independent of its decomposition. Diazomethane is used after its preparation in ether or in ether that contains traces of ethanol. It is rarely prepared and applied to other solvents which may include dichloromethane. Diazomethane is related to hydrogen cyanide and formaldehyde in its annotation.
Uses
It is used as a methylating agent especially for acidic compounds which may include enols, phenols, and carboxylic acids.
Description
Diazomethane is a flammable, yellow gas, or aliquid under pressure. Molecular weight = 42.05; Boilingpoint = 222.7℃; Freezing/Melting point = -145℃;Autoignition temperature = 100℃ (explodes). HazardIdentification (based on NFPA-704 M Rating System):Health 4, Flammability 3, Reactivity 3. Decomposes inwater; reaction.
Uses
It is used in organic synthesis as a methylating agent to methylate acidic compoundssuch as carboxylic acids and phenols. Itis used in trace environmental analysis tomethylate chlorophenoxy acid herbicides.
Uses
Powerful methylating agent for acidic compounds such as carboxylic acids, phenols, enols; not manufactured for sale and distribution because of toxicity and explosivity
Uses
Powerful methylating agent for acidic Compounds such as carboxylic acids, phenols, enols. For syntheses with diazomethane see the reviews by Smith, Chem. Rev. 23, 193 (1938); Eistert, Z. Angew. Chem. 54, 99, 124 (1941) translated by Spangler in Newer Methods of Preparative Organic Chemistry (New York, 1948) p 513; J. S. Pizey, Synthetic Reagents vol. 2 (John Wiley, New York, 1974) pp 65-142.
General Description
Yellow gas with a musty odor. Highly toxic by inhalation Shipped as a liquid under pressure.
Preparation & Synthesis
Preparation
Diazomethane was generated with a diazomethane-generating glassware kit (Aldrich). A solution of N-methyl-N-nitroso-4-toluenesulfonamide (Diazald, 2.23 g, 10.4 mmol) in ether (24 mL) was added dropwise to a mixture of KOH (1.75 g, 31.2 mmol) in H2O (18 mL), ether (4 mL), and 2-(2-ethoxyethoxy)ethanol (18 mL) kept at 70 ºC. The ethereal solution of diazomethane was continuously distilled into a flask that was ready to use for the next reaction.