Here's the way I see this;
Sanchez holds the cards here - if he wants to go to Chelsea, he'll either go to Chelsea for what they consider a fair price in the summer, or he'll stink the dressing room out for a season and go next summer, costing Arsenal the transfer fee and delaying their buying a replacement in a rapidly inflating market. Same if he wants to go to us or any other club.
There's a poster on here that seems convinced he has his heart set on going to play for Juve in a second rate league for half the money, but I doubt he'll choose them over a PL club. He's already in the UK and the wages are higher here than anywhere bar the two big Spanish clubs.
Chelsea won't pay £50m - they're shrewd when it comes to transfers and it's not value for money for them with Willian, Pedro, Costa and Hazard at the club already and the centre back and wing back positions more in need of upgrades and depth.
Juve won't pay £50m unless they have a big outgoing - their yearly revenue is less than Chelsea's and they have a new stadium to pay off. They also won't offer him the wages he wants - parity with Arsenal at best, they can't afford to have all of their top players banging down the door demanding a payrise and so won't break their pay structure.
Bayern have just signed Julien Brandt and are already well stacked in the forward positions, they won't give him the wages he wants either. They won't be offering £50m.
The rags might - they're likely to lose big conk to LA and will badly need a goalscorer. So what? If they want to blow money then let them - we have other positions that need attention far more than we need Sanchez. No guarantee he'll sign for them either - they still have a major rebuild needed and don't look like challenging for the league anytime soon.
Liverpool can't pay his wages.
Spurs are a no go, as are Barca.
Madrid won't want a Barca cast off.
PSG are set going forward with Di Maria, Cavani and Draxler.
Honestly - I can't see another club offering anywhere near that money for him and he's available on a free in 13 months, so why the fuck would we do it, when he doesn't even play in a position that we need to prioritise for transfers this summer?