CV 251 then DL 2570 at O'Hare
Anchorage → Chicago → Boston
Timetable, Chicago time
21:32CV 251 from Anchorage at the gate
10:35DL 2570 to Boston leaves the gate
13 h 03 apart on the timetable, overnight
DL 2570 leaves 13 h 03 after CV 251 arrives on the timetable: more than half a day, so not a connection we count.