Adding acetic acid (1 equiv) to the one-pot annulation reaction either at the beginning or during the reaction did not improve the yield indicating that the in situ generated acetic acid was sufficient for the whole process to occur. Running the reaction with CsOPiv (1.2 equivalents) as a base gave results very similar to CsOAc. Overall, these findings show that the optimized conditions for the annulation reaction (Table , entry 14) do not need to be modified.