Ibuprofen Isolation Lab Report

Isolation of Ibuprofen:
Fifteen 200 mg ibuprofen tablets were used, which was 3.37g (16.34 mmol, 112.3%) ibuprofen. This amount of ibuprofen was submerged in 25 mL of acetone and stirred vigorously for 5 minutes to dissolve. Red coatings of the tablet were separated and vacuum filtration was utilized to dissolve all insoluble components. The melting point range of the crude ibuprofen was 72.4-73.9°C. The major bands from the IR are, FTIR: sp3 O-H stretch, about 3200-2500 cm-1 (b, m); sp3 C-H stretch, 2991-2868 cm-1 (sh, m); sp2 =C-H stretch, 3100-3000 cm-1 (sh, w); sp2 C=O stretch, 1701 cm-1 (sh, s); and sp2-sp2, aromatic, C=C stretch (in ring), 1507 cm-1 (s, m).

Formation of Diastereomeric Salts:
30 mL of 0.25 M sodium hydroxide was added to the flask that contained the crude ibuprofen. This flask was heated to 85°C with the addition of 0.9 mL of S-(-)-α-phenethylamine (d=0.94 g/mL, 6.981 mmol). The crude salt was collected via vacuum filtration for 30 minutes and the percent yield of the salt formation was 98.688 %.

This beaker was heated in a hot water bath until the solid dissolved in the solution and was cooled in an ice water bath for 15 minutes. Crystals were gathered via vacuum filtration and the stir bar was removed. The mass of the final product was 0.52g and 57.33 % recovery, with a melting point of 166.5-170.6