LA 6139 then MS 9324 at San Francisco
Boston → San Francisco → Washington
Timetable, San Francisco time
23:58LA 6139 from Boston at the gate
23:20MS 9324 to Washington leaves the gate
23 h 22 apart on the timetable, overnight
MS 9324 leaves 23 h 22 after LA 6139 arrives on the timetable: more than half a day, so not a connection we count.