74684-95-0Relevant articles and documents
Solvolytic reactivity of pyridinium ions
Juric, Sandra,Kronja, Olga
, p. 314 - 319 (2015/05/05)
The leaving group abilities of pyridine, 4-methylpyridine, and 4-chloropyridine in SN1 solvolytic reactions have been determined by analyzing the rate constants of X,Y-substituted benzhydrylpyridinium salts obtained in various solvents. By applying the linear free energy relationship equation, log k = sf (Ef + Nf), the nucleofuge specific parameters of 4-substituted pyridine have been extracted. Because of solvation in the reactant ground state, the reactivity (nucleofugality, Nf) of a given pyridine decreases as the polarity of the solvent increases. High slope parameters (sf > 1) may be due to the spread of the energy levels of the benzhydrylium ion/pyridine pair intermediates in comparison to benzhydrylium ion/chloride pairs (sf ≈ 1). Because of slow heterolysis step of pyridinium salts in various solvents, some are stable under normal conditions.
Selectivity of stabilized benzhydrylium ions
Denegri, Bernard,Matic, Mirela,Kronja, Olga
scheme or table, p. 1440 - 1444 (2010/05/18)
Methyl carbonates (1-4-OCO2Me) and phenyl carbonates (2-4-OCO2Ph) were subjected to solvolysis in the series of aqueous ethanol, the product ratios were determined and the selectivities (k E/kw) of the correspon
SN1 reactions with inverse rate profiles
Denegri, Bernard,Minegishi, Shinya,Kronja, Olga,Mayr, Herbert
, p. 2302 - 2305 (2007/10/03)
Carbocations may accumulate during solvolysis reactions! The fact that fast ionization followed by slow trapping of the carbocation R+ is a characteristic pattern of many solvolysis reactions requires that the generally accepted energy profiles of these reactions be revised.
