DL 400 then AA 4582 at Boston
San Francisco → Boston → Washington National
Timetable, Boston time
15:45DL 400 from San Francisco at the gate
14:30AA 4582 to Washington National leaves the gate
22 h 45 apart on the timetable, overnight
AA 4582 leaves 22 h 45 after DL 400 arrives on the timetable: more than half a day, so not a connection we count.