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A study of the acid-catalyzed loss of alkoxide and thiolate ions from alkoxide and thiolate ion adducts is presented. The acid-catalyzed breakdown of the intermediate toward products and reactants has been analyzed.

Research was conducted to examine kinetics of the reactions of methoxybenzylidene Meldrum's acid with thiolate ions, alkoxide ions, OH-, and water in aqueous DMSO. The objective was to detect the S(sub N)V intermediate in the reaction of Meldrum's acid with nucleophiles and to determine the rate constants. Results indicate that the corresponding intermediates accumulate to detectable levels in the reactions with RS- and RO- but not in those with OH- or H2O.

The reaction of CF3CH2O-adduct of alpha-nitro-beta-(2,2,2-trifluoroethoxy) stilbene with aqueous acid leads to carbon protonation, generating the corresponding acetal. The reaction of acid with the MeO-adduct of beta-methoxy-alpha-nitrostilbene leads to acid catalyzed CH3O-expulsion. A mixture of acetals are produced from a reaction between acid and CF3CH2O-adducts of beta-methoxy-alpha-nitrostilbene. Kinetic studies help determine the rate constants for these competition reactions.

Kinetic studies of the reaction of different aliphatic amines with phosphoimidazolide-activated of guanosine and cytidine (ImPN) derivatives reveal that kinetic barrier for the reaction increases with the size of the alkyl group in the aliphatic secondary amines. Kinetic data support the higher reactivity of the primary amino groups than the secondary amino groups toward ImPN. The slow reactivity accounts for the absence of substitution products of the secondary amino groups of the polyamines.

Kinetic studies of the nucleophilic vinylic substitution reactions of alpha-nitro-beta-stilbenes with various nucleophiles enable the determination of the rate constants for the elementary steps associated with the addition-elimination mechanism. Spectroscopic studies of the reaction of beta-methoxy-alpha-nitrostilbene with CF3CH2O- and of alpha-nitro-beta-(2,2,2-trifluoroethoxy)stilbene with HOCH2CH2S- enable the identification of intermediates. Resonance, steric, anomeric and electronic effects account for the influence of structure on the rate constants.

Structure-reactivity relationships in nucleophilic vinylic substitution reaction are examined.

Investigates the mechanism of nucleophilic vinylic substitution reaction. Kinetics of the reactions of methoxybenzylidenemalononitrile; Use of MeO[sub 2]CCH[sub 2]S as thiolate ions; Effect of activating substituents on rate and equilibrium constants.