14/01/2012 11:02 +0100 – Rangers had a bid turned down for the wantaway Brazilian earlier in the week but have now reached a consensus with their west London rivals.
They must now convince the 29-year-old to become Mark Hughes' first signing as manager, amid reports he may no longer wish to remain in England.
Chelsea accepted QPR's offer less than 24 hours after Gary Cahill travelled to
London to complete the formalities of his move from Bolton.
Alex, who has also been linked with Paris St Germain and Juventus, was banished from the Blues' first-team squad in November after submitting a transfer request.
His signing would represent another coup for ambitious Rangers after they
convinced Hughes to succeed Neil Warnock as manager on Tuesday.
As well as having a previous bid for Alex snubbed - reportedly £3million - they
have had offers turned down for Andy Johnson, Christopher Samba and Steven Pienaar.
Should Rangers complete Alex's signing, he will have to wait to make his debut as the club missed the deadline for Sunday's Premier League game at Newcastle, while he is ineligible for Tuesday's FA Cup third-round replay
against MK Dons.
His first game would therefore be next Saturday's league match against Wigan, which is followed by a possible FA Cup clash with Chelsea.
Speaking on Wednesday, Hughes said of Alex: "There is interest in top-quality players and the player you mention is very much in that level.''
Chelsea boss Andre Villas-Boas said 24 hours later: "We're just trying to
reach the level of proposal we think is good for the player.
"We'll present anything to the player.
"He has to make a decision. He has generated interest from a lot of clubs.''
Chelsea signed Alex from Santos in 2004 but work-permit issues saw him loaned to PSV Eindhoven for three seasons before he joined his parent club in the summer of 2007.
The Brazil international helped the club win the FA Cup in 2009 and their first
ever double the following season.
The arrival of David Luiz a year ago saw him marginalised and although he
eventually won back his place and started this season in the team, he soon fell
back behind Luiz in the pecking order, culminating in his transfer request.