UA 2089 then AA 3484 at O'Hare
San Juan → Chicago → St Louis
Timetable, Chicago time
11:47UA 2089 from San Juan at the gate
09:30AA 3484 to St Louis leaves the gate
21 h 43 apart on the timetable, overnight
AA 3484 leaves 21 h 43 after UA 2089 arrives on the timetable: more than half a day, so not a connection we count.