AA 2779 then CA 3174 at O'Hare
Boston → Chicago → Guangzhou
Timetable, Chicago time
17:36AA 2779 from Boston at the gate
13:40CA 3174 to Guangzhou leaves the gate
20 h 04 apart on the timetable, overnight
CA 3174 leaves 20 h 04 after AA 2779 arrives on the timetable: more than half a day, so not a connection we count.