AA 6486 then UA 1840 at O'Hare
Detroit → Chicago → Hartford
Timetable, Chicago time
17:29AA 6486 from Detroit at the gate
14:36UA 1840 to Hartford leaves the gate
21 h 07 apart on the timetable, overnight
UA 1840 leaves 21 h 07 after AA 6486 arrives on the timetable: more than half a day, so not a connection we count.