BR 646 then UA 5941 at O'Hare
Anchorage → Chicago → Tucson
Timetable, Chicago time
17:10BR 646 from Anchorage at the gate
15:35UA 5941 to Tucson leaves the gate
22 h 25 apart on the timetable, overnight
UA 5941 leaves 22 h 25 after BR 646 arrives on the timetable: more than half a day, so not a connection we count.