The proton transfer reaction between bis(2,4-dinitrophenyl)methane and nitrogen bases in dimethyl sulfoxide and toluene solvents
In: Canadian Journal of Chemistry, Jg. 69 (1991-03-01), Heft 3, S. 468-473
Online
serialPeriodical
Zugriff:
Rate constants have been measured for the proton and deuteron transfer reactions of bis(2,4-dinitrophenyl)methane (1) with 1,1,3,3-tetramethylguanidine (TMG) and 1,5-diazabicyclo[5.4.0]undec-7-ene (DBU) in dimethyl sulfoxide (DMSO) and toluene solvents. Equilibrium constants, primary deuterium kinetic isotope effects, and activation parameters are reported. The reaction of 1with DBU is faster than that with TMG by factors of 5 and 50 in toluene and DMSO respectively. The primary deuterium kinetic isotope effects, kH/kD = 7–9, which are independent of the polarity of the solvent, indicate an uncoupled mechanism of proton transfer and are in the "classical" region with little or no indication of a tunnelling contribution to the enthalpy of activation for these reactions. Keywords: proton transfer, bis(2,4-dinitrophenyl)methane, deuterium isotope effects.
Titel: |
The proton transfer reaction between bis(2,4-dinitrophenyl)methane and nitrogen bases in dimethyl sulfoxide and toluene solvents
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Autor/in / Beteiligte Person: | Jarczewski, Arnold ; Schroeder, Grzegorz ; Leffek, Kenneth T. |
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Zeitschrift: | Canadian Journal of Chemistry, Jg. 69 (1991-03-01), Heft 3, S. 468-473 |
Veröffentlichung: | 1991 |
Medientyp: | serialPeriodical |
ISSN: | 0008-4042 (print) ; 1480-3291 (print) |
DOI: | 10.1139/v91-070 |
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