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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.

Two kinetic processes, observed in the hydrolysis of benzylideneacetylacetone in a strong basic medium, include fast step in the reversible OH- addition to the substrate to form T(sub OH)(super -) and the rate-determining step in the carbon protonation of T(sub OH)(super -) to form the products. pH jump experiments determine rate constants for all forward and reversible steps and are compared with those of the benzylidenemalondialdehyde and benzylidene Meldrum's acid hydrolysis.

The deprotonation of arylnitromethanes by alkyl thiolate and aryloxide ions serves as basis for a study of factors affecting proton abstraction from a carbon acid. The kinetic study points to the hydrogen-bonding ability of the central atom and, where the former is negligible, the demand for partial transition state desolvation of the base as the two strongest such factors. The similarityin the transition state imbalances of this reaction with that of amines suggestthat they are not characteristic of the thiolate ions but of the acid-base interactions that affect nucleophilic additions but not proton transfers.