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Product Name: Trimethyl Orthoformate
Synonyms: Methyl orthoformate, Orthoformic acid trimethyl ester
Chemical Formula: C4H10O3
Molecular Weight: 106.1 g/mol
CAS Number: 149-73-5
Recommended Use: Used as a reagent for methylation and protection of reactive groups in organic synthesis, industrial chemical manufacturing
Supplier Details: Manufacturer address and emergency contact numbers provided on package
Emergency Phone Number: Always check packaging for region-specific emergency contacts
GHS Classification: Flammable Liquid Category 2, Acute Toxicity (Oral) Category 4, Eye Irritation Category 2A
Signal Word: Danger
Hazard Statements: Highly flammable liquid and vapor. Harmful if swallowed. Causes serious eye irritation.
Pictograms: Flame, Exclamation mark
Precautionary Statements: Keep away from heat, sparks, open flames, and hot surfaces. No smoking. Wash face and hands thoroughly after handling. Use explosion-proof equipment and wear proper eye protection.
Potential Health Effects: Inhalation of vapor may irritate the respiratory tract. Ingestion can cause nausea, vomiting, and central nervous system depression. Skin contact may lead to mild irritation. Eyes exposed can suffer moderate to severe irritation.
Environmental Hazards: Avoid release to the environment.
Chemical Name: Trimethyl Orthoformate
Concentration: 99% or greater
Impurities/Other Ingredients: Methanol (minor impurity, typically under 1%), Water (trace amount)
CAS Number: 149-73-5
EC Number: 205-745-7
Inhalation: Move affected person to fresh air. Allow to rest in a position comfortable for breathing. Seek medical attention if symptoms develop such as dizziness, headache, or respiratory discomfort.
Skin Contact: Remove contaminated clothing. Rinse skin immediately with plenty of water for at least 15 minutes. If irritation develops or persists, get medical attention.
Eye Contact: Rinse cautiously with water for several minutes. Remove contact lenses if present and easy to do. Continue rinsing. Seek medical advice if irritation continues or vision is affected.
Ingestion: Rinse mouth with water. Do not induce vomiting. Give small amounts of water if the victim is conscious. Seek medical assistance right away. Do not give anything by mouth to an unconscious person.
Most important symptoms/effects: Respiratory irritation, gastrointestinal upset, eye and skin irritation, possible central nervous system effects from ingestion orheavy inhalation.
Suitable Extinguishing Media: Use dry chemical, carbon dioxide, alcohol-resistant foam. Water spray may also be used but can spread the liquid if sprayed directly.
Unsuitable Extinguishing Media: Do not use a solid water stream as it may spread material.
Specific Hazards: Extremely flammable vapor may form explosive mixtures with air. Containers exposed to fire can burst. Vapors are heavier than air and spread along ground—they may travel to a source of ignition and flash back.
Protective Equipment and Precautions: Wear full protective gear, self-contained breathing apparatus to prevent inhalation of toxic vapors produced by combustion.
Fire Fighting Instructions: Try to move containers away from fire area if it can be done without risk. Cool storage vessels with water spray. Prevent fire-extinguishing waters from getting into drains or natural water sources.
Decomposition Products: Methanol, carbon monoxide, carbon dioxide, formaldehyde when burning.
Personal Precautions: Evacuate unnecessary personnel. Avoid breathing vapors. Use proper eye/skin protection and adequate ventilation. Remove all sources of ignition. Ground and bond containers during transfer.
Environmental Precautions: Prevent further leakage or spillage if safe to do so. Do not discharge into drains, sewers, waterways. Notify authorities in case of large spill.
Methods for Containment and Cleaning Up: Absorb spill with inert material such as dry sand, earth, or vermiculite. Place contaminated material in a chemical waste container for disposal. Clean area with plenty of water after material pickup is complete. Thoroughly ventilate area. Dispose of according to local, regional, and national regulations.
Handling: Keep container tightly closed. Use only in a well-ventilated place. Avoid contact with eyes, skin, and clothing. Do not breathe vapor or mist. No smoking, eating, or drinking in working area. Use spark-proof tools and explosion-proof equipment. Properly ground and bond receiving containers.
Storage: Store in a cool, dry, well-ventilated place away from heat sources, open flames, sparks or other ignition sources. Keep away from incompatible substances such as acids, oxidizers, and moisture. Keep containers tightly sealed when not in use. Segregate from foods and beverages. Prevent static discharge buildup by using proper grounding procedures.
Specific end uses: Chemical synthesis in controlled industrial and laboratory settings.
Occupational Exposure Limits: No official exposure limits set for trimethyl orthoformate; watch out for methanol, which is sometimes present as an impurity (OSHA PEL for methanol: 200 ppm TWA; ACGIH TLV: 200 ppm TWA, 250 ppm STEL).
Engineering Controls: Use local exhaust ventilation to keep airborne concentrations below exposure limits. Eye wash stations and emergency safety showers required in the work area.
Personal Protective Equipment:
Gloves made from resistant material such as nitrile or butyl rubber.
Protective chemical goggles and face shield.
Lab coats, long pants, and closed-toed shoes.
Use NIOSH-approved respirator where exposure limits may be exceeded or ventilation is insufficient.
Hygiene Measures: Wash thoroughly after handling, before eating, drinking, or using restroom. Remove contaminated clothing and launder before reuse.
Appearance: Clear, colorless liquid
Odor: Fruity, pungent odor
Odor Threshold: Not determined
pH: Not applicable
Melting Point/Freezing Point: -56°C
Boiling Point: 103°C
Flash Point: 6°C (closed cup)
Evaporation Rate: Not determined
Flammability: Highly flammable
Explosive Limits: Lower 1.6% (V), Upper 16% (V)
Vapor Pressure: 54 hPa at 20°C
Vapor Density: 3.7 (air = 1)
Relative Density: 0.96 at 20°C (water = 1)
Solubility: Reacts with water, completely miscible with most organic solvents
Partition coefficient (log Kow): -0.26 (calculated)
Auto-ignition Temperature: 183°C
Decomposition Temperature: Not determined
Viscosity: 0.45 mPa.s at 25°C
Chemical Stability: Stable under recommended storage and handling conditions.
Possibility of Hazardous Reactions: Reacts with water, acids, and strong oxidizers. Forms methanol and formaldehyde on contact with moisture.
Conditions to Avoid: Heat, sparks, flames, static electricity, exposure to water vapor, and incompatibles.
Incompatible Materials: Strong acids, oxidizing agents, water, and strong alkalis.
Hazardous Decomposition Products: Methanol, formaldehyde, carbon monoxide, carbon dioxide.
Polymerization: Not likely under normal conditions but avoid adding acids which may catalyze decomposition.
Routes of Exposure: Inhalation, skin and eye contact, ingestion.
Acute Toxicity: Oral LD50 (rat): 1,670 mg/kg. Inhalation LC50 (rat): > 21 mg/L (4 h). Skin irritation may develop after direct contact.
Chronic Effects: Prolonged or repeated exposure can cause symptoms of central nervous system depression, liver and kidney damage due to metabolite methanol and formaldehyde.
Eye Damage/Irritation: Severe eye irritation.
Respiratory or Skin Sensitization: No known sensitization.
Mutagenicity/Carcinogenicity: No current studies indicate carcinogenic or mutagenic properties.
Other Effects: Inhalation may cause headaches, fatigue, nausea, and dizziness. In large doses, ingestion or heavy exposure may cause blindness due to methanol metabolite if not treated promptly.
Ecotoxicity: Not considered very toxic to aquatic organisms but releases methanol and formaldehyde on hydrolysis, both of which have negative ecological impacts.
Persistence and Degradability: Rapid hydrolysis in water with formation of methanol and formaldehyde. Main component degrades quickly in the environment.
Bioaccumulative Potential: Low, log Kow -0.26.
Mobility in Soil: Likely to be highly mobile, as it is water soluble and volatile.
Other Adverse Effects: Large quantities or frequent spills can lower water quality and harm aquatic life, especially once degraded to methanol. Prevent any release to the environment.
Waste Disposal Methods: Dispose of via licensed waste disposal contractor. Do not pour down drains or mix with regular waste. Incinerate under controlled conditions in accordance with local and national regulations.
Contaminated Packaging: Flush empty container with water then offer for recycling or disposal following hazardous waste procedures. Do not reuse the container for other materials.
Environmental Precautions: Prevent leakage or release into water sources, drains, and soil.
Regulatory Requirements: Comply with all applicable federal, state, and local regulations regarding disposal.
UN Number: UN 3272
Proper Shipping Name: Esters, N.O.S. (Trimethyl Orthoformate)
Transport Hazard Class: 3 (Flammable Liquid)
Packing Group: II
Labels Required: Flammable Liquid
Special Precautions: Keep containers upright and tightly closed during transport. Avoid rough handling, breakage, and exposure to open flame or high heat.
Marine Pollutant: Not classified as a marine pollutant.
Transport in bulk according to Annex II of MARPOL and IBC Code: Not applicable.
OSHA: Classified as hazardous based on flammability, acute toxicity, and eye irritation.
TSCA: Listed in the U.S. Toxic Substances Control Act (TSCA) inventory.
EINECS: Listed (EC No. 205-745-7).
SARA Title III: Not listed in SARA 302, SARA 313 lists, but methanol impurity is reportable under SARA 313.
California Prop 65: Contains methanol, which is listed for developmental toxicity.
Other Regulations: All ingredients appear on international inventories including AICS (Australia), DSL (Canada), IECSC (China), ENCS (Japan), and KECL (Korea). Always refer to the most current country-specific regulations and consult local authorities for compliance.
