K4 523 then AA 772 at O'Hare
Anchorage → Chicago → St Louis
Timetable, Chicago time
20:33K4 523 from Anchorage at the gate
18:03AA 772 to St Louis leaves the gate
21 h 30 apart on the timetable, overnight
AA 772 leaves 21 h 30 after K4 523 arrives on the timetable: more than half a day, so not a connection we count.