Is the reaction sequence in phosphine-catalyzed [8+2] cycloaddition controlled by electrophilicity?

In the presence of multiple electrophiles, the reaction sequence is a critical mechanistic problem. Here, we report a theoretical study on the mechanism of phosphine-catalyzed [8+2] cycloaddition of heptafulvenes and allenoate. DFT calculations showed that electrophilicity is the barrier for nucleophilic attack, while it fails in the prediction of priority. [ABSTRACT FROM AUTHOR]