AC 523 then BR 643 at O'Hare
Montréal → Chicago → Anchorage
Timetable, Chicago time
15:00AC 523 from Montréal at the gate
11:55BR 643 to Anchorage leaves the gate
20 h 55 apart on the timetable, overnight
BR 643 leaves 20 h 55 after AC 523 arrives on the timetable: more than half a day, so not a connection we count.