UA 2496 then CV 12 at O'Hare
Boston → Chicago → Luxembourg
Timetable, Chicago time
17:05UA 2496 from Boston at the gate
14:55CV 12 to Luxembourg leaves the gate
21 h 50 apart on the timetable, overnight
CV 12 leaves 21 h 50 after UA 2496 arrives on the timetable: more than half a day, so not a connection we count.