Determination of proton affinities from the kinetics of proton transfer reactions. VII. The proton affinities of O2, H2, Kr, O, N2, Xe, CO2, CH4, N2O, and CO

1980 ◽  
Vol 73 (10) ◽  
pp. 4976-4986 ◽  
Author(s):  
D. K. Bohme ◽  
G. I. Mackay ◽  
H. I. Schiff
Keyword(s):  
Proton Transfer ◽  
Transfer Reactions ◽  
Proton Affinities ◽  
Proton Transfer Reactions ◽  
Kinetics Of

Determination of the proton affinity from the kinetics of proton transfer reactions. VI. The relative proton affinities of N2, Xe, and CO2

1976 ◽  
Vol 64 (12) ◽  
pp. 4887-4891 ◽  
Author(s):  
F. C. Fehsenfeld ◽  
W. Lindinger ◽  
H. I. Schiff ◽  
R. S. Hemsworth ◽  
D. K. Bohme
Keyword(s):  
Proton Transfer ◽  
Proton Affinity ◽  
Transfer Reactions ◽  
Proton Affinities ◽  
Proton Transfer Reactions ◽  
Kinetics Of

Determination of Proton Affinity from the Kinetics of Proton Transfer Reactions. I. Relative Proton Affinities

1971 ◽  
Vol 55 (12) ◽  
pp. 5480-5484 ◽  
Author(s):  
A. E. Roche ◽  
M. M. Sutton ◽  
D. K. Bohme ◽  
H. I. Schiff
Keyword(s):  
Proton Transfer ◽  
Proton Affinity ◽  
Transfer Reactions ◽  
Proton Affinities ◽  
Proton Transfer Reactions ◽  
Kinetics Of

Determination of proton affinity from the kinetics of proton transfer reactions. II. Kinetic analysis of the approach to the attainment of equilibrium

1973 ◽  
Vol 58 (8) ◽  
pp. 3504-3518 ◽  
Author(s):  
D. K. Bohme ◽  
R. S. Hemsworth ◽  
H. W. Rundle ◽  
H. I. Schiff
Keyword(s):  
Proton Transfer ◽  
Kinetic Analysis ◽  
Proton Affinity ◽  
Transfer Reactions ◽  
Proton Transfer Reactions ◽  
Kinetics Of

Determination of the proton affinity from the kinetics of proton transfer reactions. IV The equilibrium O2H++H2⇄ H3++O2 and the relative proton affinity of O2 and H2

1973 ◽  
Vol 59 (12) ◽  
pp. 6405-6411 ◽  
Author(s):  
P. F. Fennelly ◽  
R. S. Hemsworth ◽  
H. I. Schiff ◽  
D. K. Bohme
Keyword(s):  
Proton Transfer ◽  
Proton Affinity ◽  
Transfer Reactions ◽  
Proton Transfer Reactions ◽  
Kinetics Of

Determination of proton affinity from the kinetics of proton transfer reactions. III. The measurement of the equilibrium constant at various temperatures

1973 ◽  
Vol 59 (1) ◽  
pp. 61-69 ◽  
Author(s):  
R. S. Hemsworth ◽  
H. W. Rundle ◽  
D. K. Bohme ◽  
H. I. Schiff ◽  
D. B. Dunkin ◽  
...  
Keyword(s):  
Proton Transfer ◽  
Equilibrium Constant ◽  
Proton Affinity ◽  
Transfer Reactions ◽  
Proton Transfer Reactions ◽  
Kinetics Of

A Potentiometric Study on Proton-Transfer Equilibria and Cationic Conjugation in Pyridine N-Oxide Systems in Acetone and Methanol

1996 ◽  
Vol 49 (9) ◽  
pp. 931 ◽  
Author(s):  
L Chmurzynski ◽  
E Kaczmarczyk ◽  
M Nesterowicz ◽  
G Wawrzyniak ◽  
Z Warnke
Keyword(s):  
Proton Transfer ◽  
Equilibrium Constants ◽  
Proton Donor ◽  
Heterocyclic Amines ◽  
Transfer Reactions ◽  
Oxide Systems ◽  
Experimental Systems ◽  
Proton Transfer Reactions ◽  
Potentiometric Titration Method

The potentiometric titration method has been used to study the equilibria of cationic in sytems formed by substituted pyridine N-oxides in the polar, non-aqueous solvents acetone and methanol. For comparison, the systems with trimethylamine N-oxide as a representative of aliphatic amine N-oxides and pyridine representing parent heterocyclic amines were also studied. The cationic heteroconjugation constants, i.e. the equilibrium constants for conjugation reactions between free and protonated N-bases leading to the formation of unsymmetric BHB'+ cations, were determined in experimental systems with and without proton transfer. It was found that there were significant differences in the values of the cationic heteroconjugation constants determined in these two acid-base systems. The proton-transfer reactions limit and even preclude the determination of the cationic heteroconjugation constants. On this basis it was concluded that the heteroconjugation constants should be determined in systems without proton transfer. In such systems, in the amphiprotic solvent methanol, cationic heteroconjugation was ascertained in all substituted pyridine N-oxide systems, the values of heteroconjugation constants being relatively low (logarithms of their values of the order of 2-2.5), and only negligible in systems involving trimethylamine N-oxide. A more pronounced tendency towards cationic heteroconjugation of the [OHO]+ type was observed in the aprotic protophobic acetone, where heteroconjugation constants were determined for all amine N-oxide systems studied including those containing protonated trimethylamine N-oxide as a proton donor. However, the values of the cationic heteroconjugation constants were found to be, in methanol likewise, relatively low (log KBHB'+ of the order of 2-3). On the contrary, a greater extent of cationic heteroconjugation equilibria was observed in methanol than in acetone in the case of systems containing pyridine, i.e. [NHO]+ type bridges formed by amine N-oxides and heterocyclic amines. In methanol the heteroconjugation constants turned out to be determinable for all such systems studied (logarithms of the equilibrium constants being of the same order as for N-oxide systems), whereas in acetone the hetero constants were indeterminable for all systems.

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