UA 4500 then UA 52 at Dulles
Detroit → Washington → Zurich
Timetable, Washington time
21:17UA 4500 from Detroit at the gate
17:25UA 52 to Zurich leaves the gate
20 h 08 apart on the timetable, overnight
UA 52 leaves 20 h 08 after UA 4500 arrives on the timetable: more than half a day, so not a connection we count.