UA 3902 then AA 492 at O'Hare
Rio De Janeiro → Chicago → Cancún
Timetable, Chicago time
17:01UA 3902 from Rio De Janeiro at the gate
10:05AA 492 to Cancún leaves the gate
17 h 04 apart on the timetable, overnight
AA 492 leaves 17 h 04 after UA 3902 arrives on the timetable: more than half a day, so not a connection we count.