A mechanistic study of the Diels-Alder reaction of isoprene with some substitutes benzalmalononitriles

This work was a kinetic study of the Diels-Alder reaction of isoprene with variously substituted benzalmalononitriles. Application of the Hammett equation, a linear free energy relationship, to the kinetic rate data yielded a value of 1.31 for rho. This was interpreted as meaning the transition state for this Diels-Alder reaction was probably of the concerted type, although the nonconcerted polar transition state could not be eliminated in one case by the data of this study.Ball State UniversityMuncie, IN 47306