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Basicity of 1,8-bis(dimethylamino)naphthalene and 1,4-diazabicyclo[2.2.2]octane in water and dimethylsulfoxide
| Content Provider | Semantic Scholar |
|---|---|
| Author | Benoit, Robert L. Lefebvre, Diane Frechette, M. |
| Copyright Year | 1987 |
| Abstract | The ionization constants of the conjugate acids of two bases widely used in synthesis, 1,8-bis(dimethylamino)naphthalene (PS), and 1,4-diazabicyclo[2.2.2]octane (DABCO), have been obtained in Me2SO and water. The partition coefficients of both bases B and their heats of solution and protonation have also been determined. The basicity of PS is dramatically reduced when passing from water to Me2SO while the basicity of DABCO remains unchanged, thus making DABCO the stronger base in Me2SO. The solvent effect on the base strength is analyzed in terms of free energy and enthalpy of transfer for B and H+, and for BH+, from water to Me2SO. The entropy-controlled much stronger solvation of PS in Me2SO is in line with that of aromatic compounds while the increased solvation of DABCO in water is due to H-bonding of its two nitrogens. PSH+, like H+, is better solvated by Me2SO while DABCOH+ does not show a definite preference for one solvent. The calculated enthalpy of solution of gaseous PSH+ is abnormally low when... |
| Starting Page | 996 |
| Ending Page | 1001 |
| Page Count | 6 |
| File Format | PDF HTM / HTML |
| DOI | 10.1139/v87-170 |
| Alternate Webpage(s) | http://chen.chemistry.ucsc.edu/DABCO.pdf |
| Alternate Webpage(s) | https://doi.org/10.1139/v87-170 |
| Volume Number | 65 |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
