Polar aprotic solvent
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]
| Solvent | Chemical formula | Boiling point | Dielectric constant | Density | Dipole moment (D) | Comment |
|---|---|---|---|---|---|---|
| Polar aprotic solvents | ||||||
| acetone | C3H6O | 56.05 °C | 21.83 | 0.7845 g/cm3 | 2.91 | reacts with strong acids and bases |
| acetonitrile | CH3CN | 81.3 - 82.1 °C | 38.3 | 0.776 g/cm3 | 3.20 | reacts with strong acids and bases |
| dichloromethane | CH2Cl2 | 39.6 °C | 9.08 | 1.3266 g/cm3 | 1.6 | |
| dimethylformamide | (CH3)2NCHO | 153 °C | 36.7 | 0.95 g/cm3 | 3.86 | reacts with strong bases |
| dimethylpropyleneurea | (CH3)2C4H6N2O | 246.5 °C | 36.12 | 1.064 g/cm3 | 4.23 | difficult to evaporate |
| dimethylsulfoxide | (CH3)2SO | 189 °C | 46.7 | 1.1 g/cm3 | 3.96 | reacts with strong bases, difficult to purify |
| ethyl acetate | C4H8O2 | 77.11°C | 6.02 | 0.902 g/cm3 | 1.88 | reacts with strong bases |
| hexamethylphosphoric triamide | [(CH3)2N]3PO | 232.5 °C | 29.6 | 1.03 g/cm3 | 5.38 | difficult to evaporate, high toxicity |
| tetrahydrofuran | C4H8O | 66 °C | 7.6 | 0.887 g/cm3 | 1.75 | polymerizes in presence of strong protic and Lewis acids |
References
- ^ Stoye, Dieter (2000). "Solvents". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a24_437. ISBN 3527306730.
- ^ 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.