Sodium hydride → HCID 71515501, compound

Participants

Reaction Conditions

Reaction Steps

Sodium hydride (60%, 6.00 g, 150 mmol) was taken up in THF (250 mL) under nitrogen atmosphere, and then a solution of 4-fluoro-N′-hydroxybenzimidamide (Step 2; 23.22 g, 150 mmol) in THF (250 mL) was added. The resulting reaction mixture was heated at 50° C. for 15 min, and then a solution of ethyl 2-hydroxy-2-(pyridin-4-yl)propanoate (Step 1; 25 g, 120 mmol) in THF (250 mL) was added. The mixture was stirred for 1 hr at 50° C. The progress of reaction was monitored by TLC using solvent system EtOAc:Hexane (7:3). After completion of reaction, the solvent was concentrated to one third of the total volume. The crude mixture was poured into ice water and extracted with EtOAc (3×500 mL). The combined organic extract was dried over Na2SO4 and concentrated under vacuum. The crude residue was washed with water several times to obtain a solid which was then washed with hexane (100 mL) followed by 50 mL of chilled ether to obtain 14 g (38%) of 1-(3-(4-fluorophenyl)-1,2,4-oxadiazol-5-yl)-1-(pyridin-4-yl)ethanol as a colorless solid. HPLC purity: 99.4%; 1H NMR (400 MHz, DMSO-d6): δ 8.58 (d, 2H, J=5.6 Hz), 8.06-8.03 (m, 2H), 7.51 (d, 2H, J=6.4 Hz), 7.39 (t, 2H, J=8.8 Hz), 7.09 (s, 1H), 1.96 (s, 3H); LC-MS m/z calculated for [M+H]+ 286.09. found 286.1.

Provenance & Evidence