Mechanochemical Diels-Alder reactions of benz(a)anthracene with tetracyanoethylene and 4-phenyl-1,2,4-triazoline-3,5-dione under impact force and shear stress

In this work, mechanochemical syntheses of benz(a)anthracene-tetracyanoethylene and benz(a)anthracene-4-phenyl- 1,2,4-triazoline-3,5-dione Diels-Alder adducts were carried out by grinding the solid reactants in a vibration ball mill and manual grinding them with a pestle in a mortar. Kinetic curves of reactant consumption were obtained. It was found that these kinetic curves are characterized by an initial induction period, the nature of which is unknown. Using the reactions of benz(a)anthracene with tetracyanoethylene and 4-phenyl-1,2,4-triazoline-3,5-dione as an example, it was shown that manual grinding the solid reactants with a pestle in a mortar leads to a significant increase in the adduct yield compared to processing the reactants in a vibration ball mill. It was found that the mechanochemical yield of the benz(a)anthracene-tetracyanoethylene adduct was more sensitive to changes in the type of mechanical force compared to the mechanochemical yield of the benz(a)anthracene-4-phenyl-1,2,4-triazoline-3,5-dione adduct.