Claudio Ranieri and Steve McClaren are also in the running to succeed the axed Bernd Schuster, but Scolari is in pole position after holding talks with Besiktas president Yildirim Demiroren in Istanbul last week.
Besiktas already have a strong Portuguese presence in their dressing room, following the acquisition of Ricardo Quaresma, one-time Liverpool target Simao Sabrosa and Hugo Almeida, and could bolster it further, in the event of Scolari taking over.
Bad move: Scolari spent eight months at Chelsea before he was sacked
Bosingwa, who arrived at Stamford Bridge at the same time as Scolari nearly three years ago, is surplus to requirements at Chelsea and would have been a makeweight in the recent deal for David Luiz, but for his wages being beyond Benfica's means.
There would be no such problem at Besiktas, who underlined their ambition by signing Spain midfielder Guti from Real Madrid last July.
Bosingwa has long been a target for Bayern Munich and could also interest Roma, who are likely to lose 33-year old right-back Marco Cassetti on a Bosman free this summer.
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Explore more:People: Jose Bosingwa, Steve McClaren Places: Istanbul, Liverpool, Spain