Triethyl borate is a colorless liquid with the formula B(OCH2CH3)3. It is an ester of boric acid and ethanol. It has few applications.[1]
It is a weak Lewis acid (AN = 17 as measured by the Gutmann–Beckett method).[2] It burns with a green flame and solutions of it in ethanol are therefore used in special effects and pyrotechnics.
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It is formed by the reaction of boric acid and ethanol in the presence of acid catalyst, where it forms according to the equilibrium reaction:
- B(OH)3 + 3 C2H5OH ⇌ (C2H5O)3B + 3 H2O
In order to increase the rate of forward reaction, the formed water must be removed from reaction media by either azeotropic distillation or adsorption. It is used as a solvent and/or catalyst in preparation of synthetic waxes, resins, paints, and varnishes. It is used as a component of some flame retardants in textile industry and of some welding fluxes.
References
- ^ Robert J. Brotherton; C. Joseph Weber; Clarence R. Guibert; John L. Little (2000). "Boron Compounds". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. ISBN 978-3-527-30673-2.
- ^ M.A. Beckett, G.C. Strickland, J.R. Holland, and K.S. Varma, "A convenient NMR method for the measurement of Lewis acidity at boron centres: correlation of reaction rates of Lewis acid initiated epoxide polymerizations with Lewis acidity", Polymer, 1996, 37, 4629–4631. doi: 10.1016/0032-3861(96)00323-0