UA 1672 then AA 3484 at O'Hare
Hartford → Chicago → St Louis
Timetable, Chicago time
14:32UA 1672 from Hartford at the gate
09:30AA 3484 to St Louis leaves the gate
18 h 58 apart on the timetable, overnight
AA 3484 leaves 18 h 58 after UA 1672 arrives on the timetable: more than half a day, so not a connection we count.