AA 2208 then CZ 2502 at O'Hare
St Louis → Chicago → Shanghai
Timetable, Chicago time
12:59AA 2208 from St Louis at the gate
01:45CZ 2502 to Shanghai leaves the gate
12 h 46 apart on the timetable, overnight
CZ 2502 leaves 12 h 46 after AA 2208 arrives on the timetable: more than half a day, so not a connection we count.