F9 45 then UA 5618 at O'Hare
Cancún → Chicago → Washington National
Timetable, Chicago time
14:45F9 45 from Cancún at the gate
14:00UA 5618 to Washington National leaves the gate
23 h 15 apart on the timetable, overnight
UA 5618 leaves 23 h 15 after F9 45 arrives on the timetable: more than half a day, so not a connection we count.