IB 341 then UA 3376 at O'Hare
Madrid → Chicago → St Louis
Timetable, Chicago time
14:55IB 341 from Madrid at the gate
11:00UA 3376 to St Louis leaves the gate
20 h 05 apart on the timetable, overnight
UA 3376 leaves 20 h 05 after IB 341 arrives on the timetable: more than half a day, so not a connection we count.