Diels-Alder reaction rate in the solid state and the evidence of the location of molecular complexes between the reagents on the reaction pathway

Abstract

The rate of reactions in the solid phase with uniform grinding of crystals of dienes, anthracene, and 9,10-dimethylanthracene, with dienophiles, tetracyanoethylene, N-phenylmaleimide, and 4-phenyl-1,2,4-triazoline-3,5-dione, has been studied. It was shown that, despite the high difference in the reaction rates in solution, the rates of these reactions in the solid phase are much closer. For anthracene-tetracyanoethylene and 9,10-dimethylanthracene-tetracyanoethylene pairs, it was concluded that their intermolecular complexes are on the reaction pathway.