Alkyl effects on equilibrium acidities of carbon acids in protic and dipolar aprotic media and the gas phase

1978 ◽  
Vol 43 (16) ◽  
pp. 3095-3101 ◽  
Author(s):  
F. G. Bordwell ◽  
John E. Bartmess ◽  
Judith A. Hautala
Keyword(s):  
Gas Phase ◽  
Carbon Acids

Marcus theory and the existence or non-existence of transition states in gas phase deprotonation of carbon acids

1984 ◽  
Vol 62 (8) ◽  
pp. 1465-1469 ◽  
Author(s):  
Saul Wolfe
Keyword(s):  
Proton Transfer ◽  
Gas Phase ◽  
Transition States ◽  
Marcus Theory ◽  
Energy Change ◽  
Transfer Reactions ◽  
Gas Phase Reactions ◽  
Proton Transfer Reactions ◽  
Carbon Acids ◽  
Computational Level

At the 3-21G (3-21G*) computational level, the intrinsic barriers associated with proton transfer between XCH2− and CH3X have been found to be essentially constant (ca. 10 kcal/mol) for X = H, F, SH, Cl. According to the Marcus rate-equilibrium treatment of proton transfer reactions, this result means that transition states should not exist for gas phase reactions [Formula: see text], when the energy change exceeds 20 kcal/mol. This prediction has been confirmed for two cases (X = H, F) in which the energy change is less than 20 kcal/mol, and two cases (X = SH, Cl) in which the energy change is greater than 20 kcal/mol.

scholarly journals A theoretical study of the limits of the acidity of carbon acids in phase transfer catalysis in water and in liquid ammonia

2013 ◽  
Vol 11 (11) ◽  
pp. 1711-1722 ◽  
Author(s):  
Ibon Alkorta ◽  
José Elguero ◽  
Roger Gallo
Keyword(s):  
Experimental Data ◽  
Gas Phase ◽  
Liquid Ammonia ◽  
Phase Transfer Catalysis ◽  
Theoretical Study ◽  
Phase Transfer ◽  
Dmso Solution ◽  
Homogeneous Set ◽  
Carbon Acids

AbstractThe acidities of a large number of carbon acids have been theoretically calculated for the gas-phase and for DMSO solution. The gas-phase values, both ΔH and ΔG, are very well correlated with the available experimental data. From the calculated ΔG values in DMSO and the pKas in the same solvent, a homogeneous set of pK a (DMSO) values was devised that was used to generate pK a (water). These last pK as were used to establish the limits of the acidity of carbon acids for reactions under PTC conditions both alkylations and H/D exchange. A step further led to the pK as in liquid ammonia and from them to the virtual use of PTC using liquid ammonia instead of water.

Comparison of gas-phase acidities of some carbon acids with their rates of hydron exchange in methanolic methoxide

2006 ◽  
Vol 19 (5) ◽  
pp. 308-317 ◽  
Author(s):  
Vincent F. DeTuri ◽  
Heinz F. Koch ◽  
Judith G. Koch ◽  
Gerrit Lodder ◽  
Masaaki Mishima ◽  
...  
Keyword(s):  
Gas Phase ◽  
Carbon Acids

Acidities of carbon acids. V. Correlation of acidities in dimethyl sulfoxide with gas-phase acidities

1975 ◽  
Vol 97 (11) ◽  
pp. 3226-3227 ◽  
Author(s):  
F. G. Bordwell ◽  
John E. Bartmess ◽  
George E. Drucker ◽  
Zafra Margolin ◽  
Walter S. Matthews
Keyword(s):  
Dimethyl Sulfoxide ◽  
Gas Phase ◽  
Carbon Acids

ChemInform Abstract: ACIDITIES OF CARBON ACIDS PART 5, CORRELATION OF ACIDITIES IN DIMETHYL SULFOXIDE WITH GAS-PHASE ACIDITIES

1975 ◽  
Vol 6 (33) ◽  
Author(s):  
F. G. BORDWELL ◽  
JOHN E. BARTMESS ◽  
GEORGE E. DRUCKER ◽  
ZAFRA MARGOLIN ◽  
WALTER S. MATTHEWS
Keyword(s):  
Dimethyl Sulfoxide ◽  
Gas Phase ◽  
Carbon Acids
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