AA 864 then AA 5318 at Charlotte
Chicago O'Hare → Charlotte → Lexington
Timetable, Charlotte time
19:52AA 864 from Chicago O'Hare at the gate
19:28AA 5318 to Lexington leaves the gate
23 h 36 apart on the timetable, overnight
AA 5318 leaves 23 h 36 after AA 864 arrives on the timetable: more than half a day, so not a connection we count.