Nah. Wheat and Lemon Chiffon (whatever that is) come pretty close, but no exact matches.
On topic: I know very little about 4e, but I imagine that there are still creatures immune to Coups-de-grace. As worded, Stunning Execution kills even those creatures without or, anything else to cleave, really. I understand that 4e is less simulationist than 3.x, but that may be a problem you want to address.