You can use ROBOCOPY. It is very simple and can also be used to delete empty folders inside large hierarchy.
ROBOCOPY folder1 folder1 /S /MOVE
Here both source and destination are folder1, as you only need to delete empty folders, instead of moving other files to different folder. /S option is to skip copying(moving, in the above case) empty folders. It is also faster as the files are moved inside the same drive.