AA 642 then UA 5620 at O'Hare
Dallas-Fort Worth → Chicago → Dayton
Timetable, Chicago time
13:10AA 642 from Dallas-Fort Worth at the gate
11:16UA 5620 to Dayton leaves the gate
22 h 06 apart on the timetable, overnight
UA 5620 leaves 22 h 06 after AA 642 arrives on the timetable: more than half a day, so not a connection we count.