What is the exact term to the management's sinister move of promoting an employee then sack him later?

A classic example is that the management want to rid a number of employees, probably a union members, but labor laws discouraged them to sack them outrightly. Now the management will promote them to a newly created section. If these employees take the bait, this section will be closed later with all conceivable justifications and they can no longer be re-assigned by the management since their previous positions have already been occupied. This will give the management all the reasons to sack these employees.What is the exact term to the management's sinister move of promoting an employee then sack him later?
That seems like an awful lot of trouble to get rid of someone. I can't imagine an employer going through all of that instead of simply firing someone.