My directory (in Linux) looks like
com are folders of the same name and the second
com holds the various files. I want the first
com removed, but the second and files in the second kept.
Rename the outer directory out of the way, move the inner one to the name you want, and then delete the (now empty) outer directory:
$ mv com to-delete $ mv to-delete/com com $ rmdir to-delete
You could also
mv com/com/* com and remove the inner directory, if you don't have too many files and none of them are dotfiles, but the above is more general and more efficient.