AA 2146 then UA 1862 at O'Hare
Boston → Chicago → Punta Cana
Timetable, Chicago time
08:00AA 2146 from Boston at the gate
07:38UA 1862 to Punta Cana leaves the gate
23 h 38 apart on the timetable, overnight
UA 1862 leaves 23 h 38 after AA 2146 arrives on the timetable: more than half a day, so not a connection we count.