Acetic Acid → HCID 16110667, compound

Participants

Reaction Steps

2-(1-(tert-Butyldimethylsilyloxy)-7-phenylheptyl)oxazole-5-carboxylic acid (281 mg, 6.673 mmol) was dissolved in a mixture of MeOH:toluene (4 mL: 10 mL), cooled to 0° C. and TMSCHN2 (2 M in hexanes, 3 equiv) was added dropwise under Ar. The reaction mixture was stirred at room temperature for 0.5 h before it was cooled to 0° C. and acetic acid was added dropwise until the solution turned from yellow to clear. The mixture was evaporated in vacuo and the resulting solid was dissolved in EtOAc. The solution was washed with saturated aqueous NaHCO3, washed with saturated aqueous NaCl and dried over Na2SO4. Evaporation in vacuo yielded the crude ester which was purified by flash chromatography (10-30% EtOAc/hexanes) to afford the pure ester as a clear oil (225 mg, 78%): 1H NMR (CDCl3, 500 MHz) δ 7.78 (s, 1H), 7.36-7.33 (m, 2H), 725-7.23 (m, 3H), 4.92 (t, 1H, J=7.0 Hz), 3.98 (s, 3H), 2.67 (t, 2H, J=7.5 Hz), 2.12-1.94 (m, 2H), 1.72-1.67 (m, 2H), 1.53-1.43 (m, 6H), 0.98 (s, 9H), 0.17 (s, 3H), 0.08 (s, 3H); 13C NMR (CDCl3, 125 MHz) δ 169.0, 158.5, 143.1, 142.6, 134.5, 128.8, 128.6, 126.0, 69.1, 52.5, 36.7, 36.3, 31.8, 29.5, 26.1, 26.1, 25.4, 18.6, −4.6, −4.8.

Provenance & Evidence