AN AXIOMATIC MODEL OF THE INTRAMOLECULAR DIELS-ALDER FURAN REACTION

An axiomatic model has been created for the intramolecular Diels-Alder furan (IMDAF) reaction. The model is based on the energetics of implicit transition states, which are deduced from explicit starting material and product conformations. These explicit conformations are obtained by a combination of the WIZARD and MM2 programs. The model gives good quantitative agreement for 15 out of 16 IMDAF reactions and affords a good qualitative agreement for the remaining reaction. In several cases, the model was used to make predictions about as yet untried reactions, and in all but one case, the model was successful in predicting the results of the reactions. The technique of implicit transition-state modeling is not based on any specific characteristics of the IMDAF reaction and should provide a new and rapid method for modeling many classes of reactions.