DL 2646 then DL 5704 at Boston
Chicago O'Hare → Boston → Washington National
Timetable, Boston time
23:08DL 2646 from Chicago O'Hare at the gate
21:45DL 5704 to Washington National leaves the gate
22 h 37 apart on the timetable, overnight
DL 5704 leaves 22 h 37 after DL 2646 arrives on the timetable: more than half a day, so not a connection we count.