AA 3415 then UA 3376 at O'Hare
Moline → Chicago → St Louis
Timetable, Chicago time
18:24AA 3415 from Moline at the gate
11:00UA 3376 to St Louis leaves the gate
16 h 36 apart on the timetable, overnight
UA 3376 leaves 16 h 36 after AA 3415 arrives on the timetable: more than half a day, so not a connection we count.