IB 5270 then FR 4585 at Barcelona
Mahón → Barcelona → Porto
Timetable, Barcelona time
10:15IB 5270 from Mahón at the gate
09:25FR 4585 to Porto leaves the gate
23 h 10 apart on the timetable, overnight
FR 4585 leaves 23 h 10 after IB 5270 arrives on the timetable: more than half a day, so not a connection we count.