Reactions of unsaturated aldehydes with cyclopentadiene in solvents of various polarities

The rate constants of cycloaddition of cyclopentadiene to unsaturated aldehydes in different solvents cannot be correlated with a single parameter, in particular, the Brownstein parameter. The data set can be fitted only by multiparameter equations in which the decisive factor increasing the reaction rate is the capability of a solvent for electrophilic solvation. The same parameter also governs the ratio of the endo and exo isomers of the addition product.     

Effect of the Reactant Ratio on the Kinetics of Methanolysis of Acyl Chlorides

The apparent second-order rate constants for the reaction of methacryloyl chloride with methanol regularly increase on raising the acyl chloride-to-alcohol ratio. The variation of the rate constants is described by the Michaelis-Menten equation, indicating that the process involves initial formation of an associate with a probable structure of charge-transfer complex (CTC). Thermodynamic parameters of the CTC formation and rate constants and activation parameters for the transformation of CTC into the products have been determined.     

Solvent Effect on the Rate of Dimerization of Cyclopentadiene

The rate of dimerization of cyclopentadiene and some other cycloaddition reactions is determined by electrophilic solvation of the substrate with some contribution of other solvation factors, primarily nonspecific solvation. The corresponding dependence is described by multiparameter equations.