B6 811 then G7 3376 at O'Hare
Boston → Chicago → St Louis
Timetable, Chicago time
19:17B6 811 from Boston at the gate
11:00G7 3376 to St Louis leaves the gate
15 h 43 apart on the timetable, overnight
G7 3376 leaves 15 h 43 after B6 811 arrives on the timetable: more than half a day, so not a connection we count.