Portland is 5 hours behind Santiago
Best overlap: 1:00 PM to 6:00 PM in Santiago is 8:00 AM to 1:00 PM in Portland.
1:00 PM to 6:00 PM in Santiago is when Portland is also working, at 8:00 AM to 1:00 PM their time. You get roughly 5 hours of shared time, so aim for the middle of that window to keep the call comfortable for both teams.