The Citizens have been strongly linked with a move for the Chile international but reportedly saw a bid of £50m for his services rejected by the Gunners.
A swap deal involving City's Raheem Sterling could still be on the cards, though, and while De Bruyne admits he is not privy to the transfer dealings at the Etihad Stadium, he is hopeful of calling Sanchez his team-mate from this weekend onward.
"He [Sanchez[ is a very good player, obviously but I don't know what's happening about the other transfers,” De Bruyne told Sky Sports.
"I think City is doing the business perfectly this summer and if they want him they will try everything to get him. And if he comes to us that's a good addition."
De Bruyne knows from his own experience that it is better to complete a transfer to a new club sooner, rather than later.
He added: "A quick transfer is good. If it drags on it can be annoying and I had to wait two or three weeks to join City.
"Every time you go home everyone asks what's happening? You say you're going, then the next day you say you're staying - it can be annoying.
"But everyone needs to be happy, both teams, the players. But when it's over, everyone is relieved."