Complex sentence: Ocean reached out to rappers André 3000 and Big Boi of hip hop duo OutKast to appear on "Pink Matter", but the former did not want to reunite with Big Boi as a duo on another artist's album.
Split into simpler sentences: Ocean reached out to rappers André 3000 and Big Boi of hip hop duo OutKast to appear on "Pink Matter". However, André 3000 did not want to reunite with Big Boi as a duo on another artist's album.