BR 646 then UA 1172 at O'Hare
Anchorage → Chicago → Toronto Pearson
Timetable, Chicago time
17:10BR 646 from Anchorage at the gate
13:57UA 1172 to Toronto Pearson leaves the gate
20 h 47 apart on the timetable, overnight
UA 1172 leaves 20 h 47 after BR 646 arrives on the timetable: more than half a day, so not a connection we count.