Diels-Alder reaction is paradigmatic and was extensively studied experimentally and theoretically. The textbook example is the reaction of ethene as a dienophile with 1,3butadiene which was observed experimentally. The small system size allowed for detailed static quantum chemical (QC) and quasi-classical molecular dynamics (MD) simulations of this reaction that revealed the symmetric transition state (TS) structure and the preference for a concerted mechanism (Figure ). However, many chemically interesting Diels-Alder reactions involve much bigger molecules, which may have very different behavior compared to small systems. For example, this reaction type provides a powerful route for the functionalization of fullerenes and was used to form an adduct of fullerene C60 with 2,3-dimethyl-1,3-butadiene which is the main subject of this study (Figure ). The typical fullerene size alone constitutes a challenge for QC simulations and the above system comprising fullerene and diene has 76 atoms. This imposes a big limitation on performing extensive analysis of the time-resolved mechanism of the reaction with quasi-classical MD. The MD simulations of the similarly-sized but smaller system with 57 atoms were reported to take almost 2-6 days for a single trajectory on 16 CPUs. To make matters worse, such investigations require 10 many hundreds of trajectories to obtain precise results and detect rare events. Due to the cost limitations, the propagation time is also limited and the dynamics is often propagated just long enough to see the bond formation and breaking events as defined by some cutoffs. Any interesting events occurring after this would be missed. Hence, the MD simulations of the Diels-Alder reactions with bigger molecules are very costly, require high-performance computing (HPC) facilities, and are prohibitively expensive in many cases.