Reaction #1140127

Reaction equation

(R)-naproxen

(+)-tramadol

→

(+)-tramadol (R)-naproxen

Yield 61.5%

Solvents

methanol

methanol

Conditions

Workup

1. 1
   Otherwas evaporated
2. 2
   workup.WAITThe resulting solution was left
3. 3
   workup.WAITstanding at room temperature and after 24 hours
4. 4
   Othera solid had formed
5. 5
   FiltrationThe solid was filtered off
6. 6
   Washthe filtrate was washed with 2 mL of methanol
7. 7
   Otherdried under vacuum (10 mm Hg) for 4 hours

Procedure

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%).

Source