Benatia has helped build OM's title challenging team this season.
He recalled to RMC: "De Bruyne? I tried, but he was already far ahead with Napoli.
"It's not that I wanted to sign De Bruyne at all costs, but I wanted to meet him. I wanted to talk to him, understand how he felt.
"He was free, but that doesn't mean he was free. We know free players... De Bruyne, I said to myself: 'It could really work with the manager'."
Benatia continued: "I tried two or three similar deals. I also tried with Chelsea's Wesley Fofana, who's from Marseille. I said to myself: 'He's had a lot of injuries, but could the Marseille environment, his hometown, be a good fit?'"