Polar aprotic solvent

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A polar aprotic solvent is a solvent that lacks an acidic proton and is polar. Such solvents lack hydroxyl and amine groups. In contrast to protic solvents, these solvents do not serve as proton donors in hydrogen bonding, although they can be proton acceptors. Many solvents, including chlorocarbons and hydrocarbons, are classifiable as aprotic, but polar aprotic solvents are of particular interest for their ability to dissolve salts. [1] [2] Methods for purification of common solvents are available. [3]

Solvent Chemical formula Boiling point Dielectric constant Density Dipole moment (D)Comment
Polar aprotic solvents
acetone (CH3)2CO56.1 °C21.80.785 g/cm32.91reacts with strong acids and bases
acetonitrile CH3CN82 °C38.30.776 g/cm33.20reacts with strong acids and bases
dichloromethane CH2Cl239.6 °C9.081.327 g/cm31.6low boiling point
dimethylacetamide (CH3)2NCOCH3165 °C37.80.94 g/cm33.72reacts with strong acids and bases
dimethylformamide (CH3)2NCHO153 °C36.70.95 g/cm33.86reacts with strong acids and bases
N-methylpyrrolidone CH3NCOC3H6203 °C32.31.028 g/cm34.09high boiling point
dimethylimidazolidone (CH3N)2COC2H4225 °C37.61.056 g/cm34.09high boiling point
dimethylpropyleneurea (CH3N)2COC3H6246.5 °C36.11.064 g/cm34.23high boiling point
dimethyl sulfoxide (CH3)2SO189 °C46.71.10 g/cm33.96reacts with strong bases, difficult to purify
ethyl acetate C2H5OCOCH377.1°C6.020.902 g/cm31.88reacts with strong bases
hexamethylphosphoramide [(CH3)2N]3PO232.5 °C29.61.03 g/cm35.38high boiling point, high toxicity
propylene carbonate CH3C2H3O2CO242 °C64.91.205 g/cm34.94high boiling point
pyridine C5H5N115 °C13.30.982 g/cm32.22reacts with protic and Lewis acids
sulfolane C4H8SO2286 °C43.31.27 g/cm34.8high boiling point
tetrahydrofuran C4H8O66 °C7.60.887 g/cm31.75polymerizes in presence of strong protic and Lewis acids

References [4]

  1. Stoye, Dieter (2000). "Solvents". Ullmann's Encyclopedia of Industrial Chemistry . Weinheim: Wiley-VCH. doi:10.1002/14356007.a24_437. ISBN   3527306730.
  2. John R. Rumble (ed.). "Laboratory Solvent Solvents and Other Liquid Reagents". CRC Handbook of Chemistry and Physics, 102nd Edition (Internet Version 2021). Boca Raton, FL, USA: CRC Press/Taylor & Francis.
  3. W. L. F. Armarego (2017). Purification of Laboratory Chemicals, 8th Edition. Elsevier. ISBN   9780128054567.
  4. Pfennig, A. (1995). "Kirk‐Othmer Encyclopedia of Chemical Technology, 4th Ed., Vol. 10. M. Howe‐Grant (Editor). John Wiley & Sons, New York 1993. 1022 S. mit zahir. Abb. und Tab., geb., £ 185.00". Chemie Ingenieur Technik. 67 (3): 352–353. doi:10.1002/cite.330670323. ISSN   0009-286X.

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