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]} 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)2CO	56.1 °C	21.8	0.785 g/cm3	2.91	reacts with strong acids and bases
acetonitrile	CH3CN	82 °C	38.3	0.776 g/cm3	3.20	reacts with strong acids and bases
dichloromethane	CH2Cl2	39.6 °C	9.08	1.327 g/cm3	1.6	low boiling point
dimethylacetamide	(CH3)2NCOCH3	165 °C	37.8	0.94 g/cm3	3.72	reacts with strong acids and bases
dimethylformamide	(CH3)2NCHO	153 °C	36.7	0.95 g/cm3	3.86	reacts with strong acids and bases
N-methylpyrrolidone	CH3NCOC3H6	203 °C	32.3	1.028 g/cm3	4.09	high boiling point
dimethylimidazolidone	(CH3N)2COC2H4	225 °C	37.6	1.056 g/cm3	4.09	high boiling point
dimethylpropyleneurea	(CH3N)2COC3H6	246.5 °C	36.1	1.064 g/cm3	4.23	high boiling point
dimethyl sulfoxide	(CH3)2SO	189 °C	46.7	1.10 g/cm3	3.96	reacts with strong bases, difficult to purify
ethyl acetate	C2H5OCOCH3	77.1°C	6.02	0.902 g/cm3	1.88	reacts with strong bases
hexamethylphosphoramide	[(CH3)2N]3PO	232.5 °C	29.6	1.03 g/cm3	5.38	high boiling point, high toxicity
propylene carbonate	CH3C2H3O2CO	242 °C	64.9	1.205 g/cm3	4.94	high boiling point
pyridine	C5H5N	115 °C	13.3	0.982 g/cm3	2.22	reacts with protic and Lewis acids
sulfolane	C4H8SO2	286 °C	43.3	1.27 g/cm3	4.8	high boiling point
tetrahydrofuran	C4H8O	66 °C	7.6	0.887 g/cm3	1.75	polymerizes in presence of strong protic and Lewis acids

References

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.

• 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.