After being sick for almost a week, I am back. You can't often see reductive elimination from thorium centers, because simply it is not easy to reduce Th(IV) to Th(III) or Th(II). That's why this group is focused on using a non-innocent ligand to facilitate these reactions. Here you can see the formation of a diphosphine and a thorium complex using bpy. They were able to study the kinetics of the reaction too.