AA 4780 then BR 643 at O'Hare
Buffalo → Chicago → Anchorage
Timetable, Chicago time
12:40AA 4780 from Buffalo at the gate
11:55BR 643 to Anchorage leaves the gate
23 h 15 apart on the timetable, overnight
BR 643 leaves 23 h 15 after AA 4780 arrives on the timetable: more than half a day, so not a connection we count.