UA 3902 then AA 2256 at O'Hare
Rio De Janeiro → Chicago → Punta Cana
Timetable, Chicago time
17:01UA 3902 from Rio De Janeiro at the gate
08:14AA 2256 to Punta Cana leaves the gate
15 h 13 apart on the timetable, overnight
AA 2256 leaves 15 h 13 after UA 3902 arrives on the timetable: more than half a day, so not a connection we count.