DL 2646 then AA 4520 at Boston
Chicago O'Hare → Boston → Rochester
Timetable, Boston time
23:08DL 2646 from Chicago O'Hare at the gate
21:59AA 4520 to Rochester leaves the gate
22 h 51 apart on the timetable, overnight
AA 4520 leaves 22 h 51 after DL 2646 arrives on the timetable: more than half a day, so not a connection we count.