Title: Trimethyl Borate
CAS Registry Number: 121-43-7
CAS Name: Boric acid trimethyl ester
Additional Names: methyl borate
Molecular Formula: C3H9BO3
Molecular Weight: 103.91
Percent Composition: C 34.68%, H 8.73%, B 10.40%, O 46.19%
Line Formula: B(OCH3)3
Literature References: Prepn from pyridine-boron trichloride complex: Gerrard, Lappert, Chem. Ind. (London) 1952, 53; from methanol and boric oxide, borax or boric acid: Schlesinger, J. Am. Chem. Soc. 75, 213 (1953); from methyl orthosilicates and boron halide: Wiberg, Krüerke, Z. Naturforsch. 8b, 608 (1953); from boric acid and methanol: Steinberg, Hunter, Ind. Eng. Chem. 49, 174 (1957). Several mfg processes: US 2689259; US 2884439; US 2937195 (to Callery Chem.); US 2880227 and US 2884440 (to Olin Mathieson); US 2855427 (to Am. Potash & Chem.); US 2739979 (to USAEC). Acute toxicity: H. F. Smyth et al., Am. Ind. Hyg. Assoc. J. 23, 95 (1962).
Properties: Liquid, d 0.915. bp 67-68°. Flash pt 29°C (84.2°F). Miscible with tetrahydrofuran, ether, isopropylamine, hexane, methanol, Nujol and other organic liquids. Stable in the absence of moisture, but hydrolyzes in the presence of water to methanol and boric acid. Forms an azeotrope with methanol: 70% B(OCH3)3 +30% methanol, d 0.87; bp 52-54°; flash pt 34°C (93.2°F). LD50 orally in rats: 6.14 ml/kg (Smyth).
Boiling point: bp 67-68°; bp 52-54°
Flash point: Flash pt 29°C (84.2°F); flash pt 34°C (93.2°F)
Density: d 0.915; d 0.87
Toxicity data: LD50 orally in rats: 6.14 ml/kg (Smyth)
Use: As solvent for waxes, resins, oils; catalyst in the manuf of ketones; analysis of paint and varnish ingredients; as neutron detector gas in the presence of a scintillation counter; as a promoter of diborane reactions. |