AA 4687 then DL 747 at JFK
Boston → New York → Los Angeles
Timetable, New York time
13:59AA 4687 from Boston at the gate
11:00DL 747 to Los Angeles leaves the gate
21 h 01 apart on the timetable, overnight
DL 747 leaves 21 h 01 after AA 4687 arrives on the timetable: more than half a day, so not a connection we count.