AA 2925 then Y8 7456 at O'Hare
Boston → Chicago → Shanghai
Timetable, Chicago time
21:54AA 2925 from Boston at the gate
19:10Y8 7456 to Shanghai leaves the gate
21 h 16 apart on the timetable, overnight
Y8 7456 leaves 21 h 16 after AA 2925 arrives on the timetable: more than half a day, so not a connection we count.