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Towards a comprehensive hydride donor ability scale.
It was possible to convert the large number of literature data on hydride abstraction by tritylium ions into N and s(N) parameters for the correspondinghydride donors, and construct a reactivity scale for hydrides covering more than 20 orders of magnitude.
Nucleophilicities of amino acids and peptides.
Nucleophilicity parameters N as defined by the correlation log k(20 degrees C) = s(N + E) have been determined in order to include amino acids into the most comprehensive nucleophile scales presently available, which provide a direct comparison of n-, pi-, and sigma-nucleophiles.
Nucleophilic reactivities of indoles.
The kinetics of the coupling of 2 with a large variety of indole structures have been studied in acetonitrile, leading to a ranking of this family of pi-excessive carbon nucleophiles over a large domain of the nucleophilicity scale N.
Kinetics of electrophile-nucleophile combinations: A general approach to polar organic reactivity
Abstract Benzhydrylium ions (Ar2CH+) and structurally related quinone methides are employed as reference electrophiles for comparing the nucleophilicities of a large variety of compounds, e.g.,
The DMAP-catalyzed acetylation of alcohols--a mechanistic study (DMAP = 4-(dimethylamino)pyridine).
Both the theoretical as well as the experimental studies strongly support the nucleophilic catalysis pathway for the acetylation of tert-butylacetate.
How constant are Ritchie's constant selectivity relationships? a general reactivity scale for n-, π-, and σ-nucleophiles
The kinetics of 82 reactions of benzhydrylium ions (Ar(2)CH(+)) with n-nucleophiles has been determined at 20 degrees C. Evaluation by the equation log k = s(N + E) delivered the reactivity
Guanidines: Highly Nucleophilic Organocatalysts
The nucleophile‐specific parameters N and sN, as defined by log k20 °C=sN(N+E) have been derived for the guanidines 1 a–h from the second‐order rate constants of their reactions with diarylcarbenium
Quantification of the ambident electrophilicities of halogen-substituted quinones.
With the E parameters determined in this work, it is now possible to predict rate constants for the reactions of these quinones with a large variety of nucleophiles and, thus, envisage unprecedented reactions of quinone.
Electrophilicity of 5-benzylidene-1,3-dimethylbarbituric and -thiobarbituric acids.
The kinetics of reactions of acceptor-stabilized carbanions 2a-m with benzylidenebarbituric and -thiobarbituric acids 1a-e has been determined in a dimethyl sulfoxide solution at 20 degrees C.
How nucleophilic are diazo compounds?
The kinetics of the reactions of benzhydryl cations with eight diazo compounds 1 a-g were investigated photometrically in dichloromethane and it is shown that the nucleophilic reactivities of diazonium ions cover more than ten orders of magnitude, being comparable to that of styrene on the low reactivity end and that of enamines on the high reactsivity end.