Hydrochloric Acid → HCID 67281686, compound

Participants

Reaction Steps

A suspension of 3-benzyloxy-1,2-dimethyl-6-(2,2,2-trifluoro-1-hydroxy-ethyl)-1H-pyridin-4-one (190 mg, 0.58 mmol) and methanol (30 mL) was sonicated for a few min. The addition of a 6.00 N hydrochloric acid solution (50 μL, 0.30 mmol) gave a clear solution. To the solution was added Pd/C (10 wt. %, dry basis, on activated carbon, wet, Degussa type E101 NE/W, 80 mg). The debenzylation reaction was conducted under a hydrogen pressure of 50 psi. The reaction was completed within 30 min. A CELITE™ bed was prepared on a sintered glass, and washed with 6M HCl (100 mL), followed by water (7×50 mL) and then methanol (2×50 mL) under suction. The reaction mixture was filtered through the pre-treated CELITE™ bed. The pH of the filtrate was adjusted to 6 by addition of a solution of 6.00 N sodium hydroxide (ca. 50 μL), and then concentrated in vacuo. The first crop of the solid was collected by suction filtration and washed with deionized water thoroughly to give 3-hydroxy-1,2-dimethyl-6-(2,2,2-trifluoro-1-hydroxy-ethyl)-1H-pyridin-4-one (54 mg, 39% yield, HPLC Method 1 (Example 24), RT=9.4 min, HPLC purity (peak percent area): 95.8% at λ=280 nm). 1H NMR (CD3OD) δ ppm: 6.78 (s, 1H), 5.51 (q, J=6.5 Hz, 2H), 3.80 (s, 3H), 2.50 (s, 3H); MS-ESI (m/z) 238.2 [M+1]+, 169.2, 154.2 (100%), 140.1.

Provenance & Evidence