AA 927 then CA 3174 at O'Hare
Boston → Chicago → Guangzhou
Timetable, Chicago time
21:29AA 927 from Boston at the gate
13:40CA 3174 to Guangzhou leaves the gate
16 h 11 apart on the timetable, overnight
CA 3174 leaves 16 h 11 after AA 927 arrives on the timetable: more than half a day, so not a connection we count.