Tramadol → (+)-tramadol (R)-naproxen

Participants

Reaction Steps

A solution of (R)-naproxen (925 mg, 4.02 mmol) in 3 mL of methanol was added to a solution of (+)-tramadol (530 mg, 2.01 mmol) in 1 mL of methanol. The mixture was stirred for 10 minutes and about half of the solvent was evaporated. The resulting solution was left standing at room temperature and after 24 hours a solid had formed. The solid was filtered off, the filtrate was washed with 2 mL of methanol and dried under vacuum (10 mm Hg) for 4 hours to give the methanol solvate of the 1:2 co-crystal of (+)-tramadol-(R)-naproxen as crystalline white needles (610 mg, 42%).

Provenance & Evidence