Application of the Woodward-Hoffman rules to a [14+2] cycloaddition (follow up)
For reactions in the excited state, a modified statement of the Woodward Hoffman rule applies:


  A pericyclic change in the first excited state is symmetry allowed when the total number of (4q+2)s and (4r)a components is even.


The only difference is that we're now looking for the total to be even rather than odd.