Forum:Tributing 2

Can you tribute monsters like Morphtronic Clocken during your opponent's turn? And/or before they use a spell or trap effect that targets it? I was dueling my friend and he had a Clocken with a good amount of counters, and I used interdimensional warp to take control of it with intent of sacrificing clocken. He tributed it when I activated it, ending me. Is that legal?