BR 642 then UA 5258 at O'Hare
Anchorage → Chicago → Des Moines
Timetable, Chicago time
09:02BR 642 from Anchorage at the gate
21:25UA 5258 to Des Moines leaves the gate
12 h 23 apart on the timetable
UA 5258 leaves 12 h 23 after BR 642 arrives on the timetable: more than half a day, so not a connection we count.