Reactions of Unsaturated Aldehydes with Cyclopentadiene in Solvents of Various Polarities

摘要

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.