Acetic Anhydride → HCID 71060717, compound

Participants

Reaction Steps

To a solution of tert-butyl 4-(1-hydroxy-2-nitrohexyl)-3-(1,2,3,4-tetrahydroisoquinoline-2-carbonyl)benzoate (632 mg, 1.31 mmol) in THF (3 mL) was added acetic anhydride (0.136 mL, 1.44 mmol) and a crystal of DMAP (−5 mg). After stirring at room temperature for 30 min, the reaction mixture was concentrated in vacuo. The residue was suspended in DCM (3.0 mL) and DMAP (192 mg, 1.57 mmol) was added. After stirring at room temperature overnight, the reaction mixture was diluted with DCM and washed with brine. The aqueous layer was back-extracted with DCM and the pooled organic layers were dried over anhydrous sodium sulfate and concentrated in vacuo. The residue was purified by flash chromatography (Isco 40 g column eluting with 0-25% EtOAc/hexanes) to give the title compound (485 mg, 80%) as a colorless oil. 1H NMR (CDCl3, 1:1 mixture of amide rotamers) δ 8.12-8.09 (m, 1H), 8.01-8.00 (m, 1H), 7.97 (s, 0.5H), 7.81 (s, 0.5H), 7.46 (d, J=8 Hz, 0.5H), 7.39 (d, J=8 Hz, 0.5H), 7.24-6.79 (m, 4H), 4.94 (s, 1H), 4.31 (s, 1H), 3.47 (t, J=6 Hz, 1H), 3.00-2.47 (m, 5H), 1.65-1.31 (m, 4H), 1.63 (s, 9H), 0.95-0.86 (m, 3H); MS(ESI+) m/z 465.3 (M+H)+.

Provenance & Evidence