Physical properties of some common organic solvents


 

  e m Y Z ET
Water 84.2  2.2  3.49  94.6  63.1
Formamide 110  3.7  0.6  83.2  56.6 
Methanol 38.6  3.46  -1.09  83.6  55.5 
Ethanol/water(80%)     0  84.8  53.6 
Ethanol 24.3  1.69  -2.03  79.6  51.9 
Isopropyl alcohol 18.3  1.66  -2.73  76.3  48.6 
Acetonitrile 36.2  3.92    71.3  46 
Dimethylsulfoxide 49  3.96    71.1  45 
Sulfolane 44  4.7    77.5  44 
t-Butanol 10.9  1.66  -3.26  71.3  43.9 
Dimethylformamide 36.7  3.86    68.5  43.8 
Acetone 20.7  2.88    65.7  42.2 
Dichloromethane 8.9  1.6    64.2  41.1 
Pyridine 12.3  2.19    64  40.2 
Chloroform 4.7  1.87    63.2   
Hexamethylphosphoramide       62.8  40.9 
Tetrahydrofuran 7.32  1.63      37.4 
Diethyl ether 4.34  1.15      34.6 
Benzene 2.28  0    54  34.5 
Toluene 2.38  0.36      33.9 
Carbon tetrachloride 2.23  0      32.5 
Hexane 1.89  0.08      30.9 

Definitions:

e = dielectric constant, a macroscopic property of the solvent as a continuous medium.

m = dipole moment, debyes, a microscopic property of the individual molecule.

Y = log(k(test solvent)/k(80%EtOH/water)) for SN1 reaction of tert-butyl chloride at 25°C. A more polar solvent makes this reaction faster, and Y more positive.

Z = energy of the photochemical excitation of methyl N-ethyl-4-pyridinecarboxylate iodide, kcal/mol, in the particular solvent.

ET = energy of the photochemical excitation of an N-phenoxypryidinium zwitterion, kcal/mol, in the particular solvent.

For both Z and ET, the stabilization of the polar reactant vs. the nonpolar excited state leads to an increase in excitation energy in polar solvents.

Solvent Properties

Back to CH 362 Home page

02/28/05 ;