AS 676 then DL 438 at Seattle
Las Vegas → Seattle → Boston
Timetable, Seattle time
12:31AS 676 from Las Vegas at the gate
11:45DL 438 to Boston leaves the gate
23 h 14 apart on the timetable, overnight
DL 438 leaves 23 h 14 after AS 676 arrives on the timetable: more than half a day, so not a connection we count.