When the catalyst amount per step was doubled to 4 mol%, the reaction times were reduced, as anticipated, for all catalysts, except BiHex. The increase in catalyst concentration had a particularly marked effect in the case of DBTDL, reducing the duration of II step to 1.5 hours and the total reaction time from 19 to 4.5 hours. Meanwhile, for both BiNDE and ZnAc the change in reaction time was modest (<10 hours), with total reaction times of approx. 20 hours.