Vincent Aboubakar netted the opener for the home side in the 17th minute at Besiktas' Vodafone Park, while Domagoj Vida scored a header five minutes later to double the lead in the first half.
In the second half, visitors came from behind with Deniz Turuc and Giuliano's goals and the match went into extra time. Cyle Larin scored the winning goal in the 102nd minute to send the Black Eagles into the final.
In another semifinal game, Fraport TAV Antalyaspor will host Aytemiz Alanyaspor on Wednesday.