AA 475 then DL 2646 at O'Hare
Los Angeles → Chicago → Boston
Timetable, Chicago time
06:56AA 475 from Los Angeles at the gate
19:45DL 2646 to Boston leaves the gate
12 h 49 apart on the timetable
DL 2646 leaves 12 h 49 after AA 475 arrives on the timetable: more than half a day, so not a connection we count.