There's more put two are yawn and sing.
There are no items that can put Pokemon to sleep, only moves like hypnosis and sleep powder.
Sadly, Porygon is unable to receive a move that can put the opponent to sleep. He can however learn the moves Lock onand Zap Cannon. This combo allows Porygon to ensure paralysis while landing a solid electric type move.
Stun Spore is a move in Pokémon Diamond, Pearl and Platinum. It can be used to put your opponent into a paralysis.
Dark hole, hypnosis, yawn, sleep powder.
put them to sleep, or paralyze them