HuagongsheHuagongshe Chemistry Print Report · For research reference only
Trimethyl borate
B(OMe)3 · trimethyl · B(OCH3)3 · TRIMETHOXYBORANE · METHYL BORATE · C3H9BO3 · Lobitridol · TriMethyl borat
Identifiers & Physical Properties
| CAS No. | 121-43-7 |
|---|---|
| Molecular formula | C3H9BO3 |
| Average molar mass | 103.92 g/mol |
| Monoisotopic mass | 104.06447455 g/mol |
| SMILES | COB(OC)OC |
| InChIKey | WRECIMRULFAWHA-UHFFFAOYSA-N |
| PubChem CID | 8470 |
| ChEBI | CHEBI:38913 |
| EC No. | 204-468-9 |
| DTXSID | DTXSID0037738 |
Chemical & Physical Properties
| Topological polar surface area | 27.7 |
|---|---|
| Hydrogen bond donors | 0 |
| Hydrogen bond acceptors | 3 |
| Rotatable bonds | 3 |
| Heavy atoms | 7 |
| Formal charge | 0 |
| Complexity | 31.7 |
| Chemical classes | Metals -> Metalloid Compounds (Boron)Flammable agents - 3rd degree |
| LogP (partition coefficient) | -1.9 |
| Density | 0.915 g/cu cmRelative density (water = 1): 0.9150.92 @ 20°C0.932 g/mL at 20 °C (lit.) |
| Color/Form | Colorless, moisture-sensitive liquidfumes in air |
| Solubility | Miscible with tetrahydrofuran, ether, isoporpylamine, hexane, methanol, nujol, and other organic liquidsMiscible with alcohol, ethersoluble in polar nonhydroxylic solventsSolubility in water: reactionMiscible with tetrahydrofuran, ether, isoporpylamine, hexane and methanol.reacts |
| Flash point | less than 80 °F (NFPA, 2010)< 80 °F (< 27 °C) (closed cup)- 7 °C8 °F |
| Boiling point | 67.5 °C68 °C68 °C @760 [mm Hg]68-69 °C (lit.) |
| Decomposition | The substance decomposes on heating or on burning producing toxic fumes including boron oxide.When heated to decomposition it emit acrid smoke and irritating fumes. |
| Melting point | -29.3 °C-29 °C-34 °C (lit.) |
| Vapor density | 3.59 (Air = 1)Relative vapor density (air = 1): 3.63.59 (vs air) |
| Vapor pressure | 137.0 [mmHg]137 mm Hg at 25 °CVapor pressure, kPa at 25 °C: 18137 [mm Hg] @25 °C147.9-148 hPa ( 20 °C) |
| Refractive index | Index of refraction: 1.3568 at 20 °C/Dn20/D 1.358(lit.) |
| Storage conditions | Store at <= 20°C. |
| Physical state | Liquid |
| Color | Colorless |
| Specific gravity | 0.915 |
| Specific heat capacity | Cp(liquid): 1.83 J/(g·K), at 25℃ |
| Hydrolytic Sensitivity | 7: reacts slowly with moisture/water |
| Sensitivity | Moisture Sensitive |
| Merck | 14,9712 |
| BRN | 1697939 |
| Exposure limits | ACGIH: TWA 200 ppmSTEL 250 ppm (Skin)OSHA: TWA 200 ppm(260 mg/m3)NIOSH: IDLH 6000 ppmTWA 200 ppm(260 mg/m3)STEL 250 ppm(325 mg/m3) |
| Dielectric constant | 8.2(20℃) |
| Stability | Stable. Incompatible with oxidizing agents. Decomposes slowly in the presence of moisture, rapidly in water. Flammable. |
| InChI | 1S/C3H9BO3/c1-5-4(6-2)7-3/h1-3H3 |
| InChIKey | WRECIMRULFAWHA-UHFFFAOYSA-N |
| SMILES | COB(OC)OC |
| CAS DataBase Reference | 121-43-7(CAS DataBase Reference) |
| EWG's Food Scores | 1 |
| FDA UNII | 82U64J6F5N |
| NIST Chemistry Reference | Boric acid, trimethyl ester(121-43-7) |
| EPA Substance Registry System | Boric acid (H3BO3), trimethyl ester (121-43-7) |
| UNSPSC Code | 12352108 |
| NACRES | NA.22 |
| GHS pictogram | GHS02,GHS07,GHS08 |
| Signal word | Danger |
| GHS hazard statements | H312-H319-H360-H335-H226 |
| GHS precautionary statements | P501-P202-P240-P261-P210-P233-P201-P243-P241-P242-P271-P264-P280-P370+P378-P308+P313-P337+P313-P305+P351+P338-P362+P364-P303+P361+P353-P304+P340+P312-P403+P233-P403+P235-P405 |
| Target organs | Eyes |
| Personal protective equipment (PPE) | Eyeshields, Faceshields, Gloves, type ABEK (EN14387) respirator filter |
| Hazard symbols | Xn,F,T |
| Risk statements (R) | 11-21-23/25-36/37/38-10-36-61-60 |
| Safety statements (S) | 16-27-36/37/39-45-25-23-2-26-53 |
| UN transport number | UN 2416 |
| Water hazard class (WGK) | 3 |
| RTECS number | ED5600000 |
| F | 21 |
| Autoignition temperature | 305°C |
| TSCA inventory status | TSCA listed |
| Hazard class | 3Acute Tox. 3 DermalAcute Tox. 3 InhalationAcute Tox. 3 OralEye Irrit. 2Flam. Liq. 2Repr. 1BSTOT SE 1 |
| Packing group | II |
| Customs code | 29209085 |
| Storage class | 3 - Flammable liquids |
| Hazardous substances data | 121-43-7(Hazardous Substances Data) |
| Toxicity | LD50 orally in rats: 6.14 ml/kg (Smyth) |
| REACH registrations | Active |
| Limited quantities | 1.0 L (0.3 gallon) (liquid) |
| Excepted quantities | Max Inner Pack (30g or 30ml) and Max Outer Pack (500g or 500ml) |
Safety & Regulations
| GHS classification | DangerH226: Flammable liquid and vapor [Warning Flammable liquids]P203, P210, P233, P240, P241, P242, P243, P280, P302+P352, P303+P361+P353, P317, P318, P321, P362+P364, P370+P378, P403+P235, P405, and P501 (click each P-code to see the statement)H225 (40.5%): Highly Flammable liquid and vapor [Danger Flammable liquids]P203, P210, P233, P240, P241, P242, P243, P260, P261, P262, P264, P264+P265, P270, P271, P280, P301+P316, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P308+P316, P316, P317, P318, P321, P330, P337+P317, P361+P364, P362+P364, P370+P378, P403+P233, P403+P235, P405, and P501 (click each P-code to see the statement) |
|---|---|
| Regulatory information | Chemical: Boric acid (H3BO3), trimethyl esterHazard Traits - Reproductive ToxicityBoric acid (H3BO3), trimethyl ester is listed on the EPA's Chemical Data Reporting (CDR) system. Manufacturers and importers of Boric acid (H3BO3), trimethyl ester are required to report information about their production and use of this chemical to the EPA under the Toxic Substances Control Act (TSCA). (40 eCFR Part 711)Status: Active Update: 01-07-2022 https://echa.europa.eu/registration-dossier/-/registered-dossier/14170Boric acid, trimethyl ester: HSNO Approval: HSR001230 Approved with controlsThe 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 | Flammable Liquid |
| Fire hazards | Excerpt from ERG Guide 129 [Flammable Liquids (Water-Miscible / Noxious)]:· HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames.Highly flammable. Gives off irritating or toxic fumes (or gases) in a fire. Vapour/air mixtures are explosive. |
| Fire potential | Flammable, fire risk ...A very dangerous fire hazard when exposed to heat, flame, or oxidizers. |
| Health hazards | Excerpt from ERG Guide 129 [Flammable Liquids (Water-Miscible / Noxious)]:· May cause toxic effects if inhaled or absorbed through skin. |
| Hazards summary | A skin and eye irritantInhalation may cause cough and sore throat[ICSC] Chronic poisoning in grazing animals where soil is high in boric acid results in vomiting, diarrhea, shock, convulsions, and paralysisPost-mortem findings include inflammation of the GI tract, liver and kidney damage, and cerebral edema[HSDB] |
| DOT ID and guide | 2416 129 |
| Reactive group | Esters, Sulfate Esters, Phosphate Esters, Thiophosphate Esters, and Borate Esters |
| EC classification | Symbol: XnR: 10-21S: (2)-23-25 |
| UN classification | UN Hazard Class: 3UN Pack Group: II |
| Special Reports | USEPA/OWRSQuality Criteria for Water 1986 Boron (1986) EPA 440/5-86-001 |
| Reactivity Alerts | Highly Flammable |
| Fire fighting | Excerpt from ERG Guide 129 [Flammable Liquids (Water-Miscible / Noxious)]:Use foam, powder, carbon dioxide. In case of fire: keep drums, etc., cool by spraying with water. NO direct contact with water. |
| First aid measures | Fresh air, rest.Rinse skin with plenty of water or shower.First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.Rinse mouth. Refer for medical attention . |
| Accidental release measures | · CALL 911. Then call emergency response telephone number on shipping paper. If shipping paper not available or no answer, refer to appropriate telephone number listed on the inside back cover.· ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area. |
| First aid | Excerpt from ERG Guide 129 [Flammable Liquids (Water-Miscible / Noxious)]:General First Aid: |
| Safe storage | Fireproof. Separated from strong oxidants and strong acids. Dry. |
| Exposure control and personal protection | · Wear positive pressure self-contained breathing apparatus (SCBA). |
| Fire fighting procedures | To fight fire use dry chemical, CO2, spray, foam.If material on fire or involved in fire: Do not extinguish fire unless flow can be stopped. Use water in flooding quantities as fog. Solid stream of water may be ineffective. Cool all affected containers with flooding quantities of water. Use "alcohol" foam, dry chemical or carbon dioxide. Keep run-off water out of sewers and water sources. |
| Cleanup methods | Collect leaking and spilled liquid in sealable containers as far as possible. Absorb remaining liquid in dry sand or inert absorbent and remove to safe place. Do NOT wash away into sewer (extra personal protection: self-contained breathing apparatus). /table/ |
| Nonfire spill response | Excerpt from ERG Guide 129 [Flammable Liquids (Water-Miscible / Noxious)]: |
| Disposal methods | SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational exposure 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, aquatic, and plant lifeand conformance with environmental and public health regulations. |
| Spillage disposal | Personal protection: filter respirator for organic vapours of low boiling point adapted to the airborne concentration of the substance. Collect leaking liquid in sealable containers. Do NOT wash away into sewer. Absorb remaining liquid in dry sand or inert absorbent. Then store and dispose of according to local regulations. |
| Preventive Measures | Do not breathe gas, fumes, vapor, or spray. Avoid contact with eyes.SRP: The scientific literature for the use of contact lenses in industry is conflicting. The benefit or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place.SRP: Local exhaust ventilation should be applied wherever there is an incidence of point source emissions or dispersion of regulated contaminants in the work area. Ventilation control of the contaminant as close to its point of generation is both the most economical and safest method to minimize personnel exposure to airborne contaminants.SRP: Contaminated protective clothing should be segregated in such a manner so that there is no direct personal contact by personnel who handle, dispose, or clean the clothing. Quality assurance to ascertain the completeness of the cleaning procedures should be implemented before the decontaminated protective clothing is returned for reuse by the workers. Contaminated clothing should not be taken home at end of shift, but should remain at employee's place of work for cleaning.For more Preventive Measures (Complete) data for TRIMETHYL BORATE (6 total), please visit the HSDB record page. |
| Environmental fate | TERRESTRIAL FATE: Trimethyl borate is rapidly hydrolyzed to boric acid and methanol in the presence of water(1,2). Hydrolysis would be expected to be the dominate fate process for trimethyl borate in the environment(SRC).AQUATIC FATE: Trimethyl borate is rapidly hydrolyzed to boric acid and methanol in the presence of water(1,2). Hydrolysis would be expected to be the dominate fate process for trimethyl borate in the environment(SRC).ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), trimethyl borate, which has a vapor pressure of 136 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Trimethyl borate is rapidly hydrolyzed to boric acid and methanol in the presence of water(3,4). Hydrolysis would be expected to be the dominate fate process for trimethyl borate in the environment(SRC). |
| Adverse effects | Neurotoxin - Other CNS neurotoxin |
| Exposure routes | The substance can be absorbed into the body by inhalation, through the skin and by ingestion. |
| Signs and Symptoms | Cough. Sore throat.Redness. Burning sensation.Redness. Pain.Burning sensation. Abdominal pain. |
| Medical Surveillance | No specific considerations are needed for boric acid or borates except for general health and liver and kidney function. /Boric acid and borates/ |
| Soil Adsorption/Mobility | Trimethyl borate is rapidly hydrolyzed to boric acid and methanol in the presence of water(1,2). Hydrolysis would be expected to be the dominate fate process for trimethyl borate in the environment(SRC). Adsorption to soil or suspended particles in water is not considered an important environmental fate for trimethyl borate(SRC). |
| Natural Pollution Sources | Borates are found in ocean water, sedimentary rocks, coal, shale, and soils(1). |
| Human Toxicity Excerpts | /SIGNS AND SYMPTOMS/ Inhalation: Cough, sore throat. Eyes: Redness, pain. Skin: Redness, burning sensation. /table//OTHER TOXICITY INFORMATION/ Harmful in contact with skin |
| Artificial Pollution Sources | Trimethyl borate's production and use as a solvent, flame retardant for textiles, dehydrating agent, brazing flux, wood preservative, catalyst, as well as it use as an intermediate for the synthesis of boron compounds and in scintillation counters(1-3) may result in its release to the environment through various waste streams(SRC). Trimethyl borate is used to treat wood where it is decomposed to boric acid upon contact with the moisture in the woodthe boric acid formed acts as a wood preservative preventing damage from wood-destroying fungi and insects(2). |
| Environmental Biodegradation | Trimethyl borate is rapidly hydrolyzed to boric acid and methanol in the presence of water(1,2). Biodegradation in not considered an important environmental fate for trimethyl borate(SRC). |
| Environmental Bioconcentration | Trimethyl borate is rapidly hydrolyzed to boric acid and methanol in the presence of water(1,2). Hydrolysis would be expected to be the dominate fate process for trimethyl borate in the environment(SRC). Bioconcentration is not considered an important environmental fate for trimethyl borate(SRC). |
| Volatilization from Water/Soil | Trimethyl borate is rapidly hydrolyzed to boric acid and methanol in the presence of water(1,2). Hydrolysis would be expected to be the dominate fate process for trimethyl borate in the environment(SRC). Volatilization from water or soil is not considered an important environmental fate for trimethyl borate(SRC). |
| State drinking water guidelines | (CA) CALIFORNIA 1000 ug/L /Boron/(NH) NEW HAMPSHIRE 630 ug/L /Boron/(ME) MAINE 1,400 ug/L /Boron/(MN) MINNESOTA 1,000 ug/L /Boron/(WI) WISCONSIN 960 ug/L /Boron/ |
| Federal drinking water guidelines | EPA 600 ug/L /Boron/ |
| F | 21 |
| Personal protective equipment (PPE) | Eyeshields, Faceshields, Gloves, type ABEK (EN14387) respirator filter |
| Water hazard class (WGK) | 3 |
| TSCA inventory status | TSCA listed |
| RTECS number | ED5600000 |
| UN transport number | UN 2416 |
| Customs code | 29209085 |
| Toxicity | LD50 orally in rats: 6.14 ml/kg (Smyth) |
| Risk statements (R) | 11-21-23/25-36/37/38-10-36-61-60 |
| Signal word | Danger |
| GHS pictogram | GHS02,GHS07,GHS08 |
| Hazard symbols | Xn,F,T |
| Safety statements (S) | 16-27-36/37/39-45-25-23-2-26-53 |
| Hazard class | 3Acute Tox. 3 DermalAcute Tox. 3 InhalationAcute Tox. 3 OralEye Irrit. 2Flam. Liq. 2Repr. 1BSTOT SE 1 |
| Storage class | 3 - Flammable liquids |
| Packing group | II |
| Target organs | Eyes |
| GHS hazard statements | H312-H319-H360-H335-H226 |
| Limited quantities | 1.0 L (0.3 gallon) (liquid) |
| Excepted quantities | Max Inner Pack (30g or 30ml) and Max Outer Pack (500g or 500ml) |
| REACH registrations | Active |
| Autoignition temperature | 305°C |
| GHS precautionary statements | P501-P202-P240-P261-P210-P233-P201-P243-P241-P242-P271-P264-P280-P370+P378-P308+P313-P337+P313-P305+P351+P338-P362+P364-P303+P361+P353-P304+P340+P312-P403+P233-P403+P235-P405 |
| Hazardous substances data | 121-43-7(Hazardous Substances Data) |
Applications & Uses
Uses
Trimethyl borate is a useful reagent in organic synthesis. It is involved in the production of resins, waxes and paints and acts as a methylation agent. As a boron source, Trimethyl borate is used to prepare flame retardants, anti-oxidants and corrosion inhibitors. It reacts with Grignard reagents followed by hydrolysis to prepare boronic acid. It is also used as a precursor of borate esters, which finds application in the Suzuki coupling reaction. It is used as neutron detector gas in the presence of a scintillation counter; as a promoter of diborane reactions.
General Description
Trimethyl borate appears as a water-white liquid. Denser than water. Vapors heavier than air. Used as a solvent and fungicide for fruit.
Preparation & Synthesis
Preparation
The preparation method of trimethyl borate1. The direct reaction between boric acid and methanol is as follows:3CH30H+H3B03→B (OCH3) 3+3H20Usually the trimethyl borate formed in the reaction forms an azeotrope with excess methanol and is distilled out together, and then the trimethyl borate is obtained by separating the azeotrope.2. The direct reaction between boron oxide and methanol is as follows:B203+6CH30H→2B (OCH3) 3+3H203. Borax, methanol and sulfuric acid are directly reacted, and the reaction formula is :Na2B4O7.1OH2O+12CH30H+2H2S04→4B (OCH3)3+2NaHS04+17H20