UA 5191 then AA 764 at Houston
Oklahoma City → Houston → Chicago
Timetable, Houston time
09:30UA 5191 from Oklahoma City at the gate
09:11AA 764 to Chicago leaves the gate
23 h 41 apart on the timetable, overnight
AA 764 leaves 23 h 41 after UA 5191 arrives on the timetable: more than half a day, so not a connection we count.