Portland is 9 hours behind Casablanca
Best overlap: 5:00 PM to 6:00 PM in Casablanca is 8:00 AM to 9:00 AM in Portland.
For a call that suits both sides, look at 5:00 PM to 6:00 PM in Casablanca / 8:00 AM to 9:00 AM in Portland. With overlap this short — around 1 hour — a recurring slot at 5:00 PM in Casablanca (8:00 AM in Portland) is worth its weight in gold. These times hold for most of the year, but Portland's daylight saving (which Casablanca doesn't use) shifts them by an hour twice annually.