UA 3532 then AA 2074 at O'Hare
Knoxville → Chicago → Boston
Timetable, Chicago time
18:43UA 3532 from Knoxville at the gate
13:37AA 2074 to Boston leaves the gate
18 h 54 apart on the timetable, overnight
AA 2074 leaves 18 h 54 after UA 3532 arrives on the timetable: more than half a day, so not a connection we count.