Acetic Anhydride → HCID 60166734, compound

Participants

Reaction Steps

Nitrostyrene 7a (182 mg, 0.55 mmol) in THF (0.7 mL) was added dropwise to a solution of Lithiumaluminium hydride (42 mg, 1.12 mmol) in THF (2 mL) under organ atmosphere at RT. Upon completion (nearly immediately) the reaction was quenched by the addition of water (42 μL), 3M NaOH (42 μL), and water (84 μL). The resulted mixture was filtered through a plug of celite, washed with DCM, and dried over K2CO3. Upon filtration the mixture was concentrated to oil and used without further purification. Acetic anhydride (58 μL, 0.62 mmol) and triethylamine (93 μL, 0.67 mmol) were added to a solution of the crude amine in DCM (5.6 mL) under an organ atmosphere at RT. After 3 h the reaction was quenched with saturated aqueous ammonium chloride and extracted with DCM (3×10 mL); combined organic fractions were washed with saturated aqueous sodiumchloride, dried over Na2SO4, filtered and concentrated. The residue was purified by column chromatography (SiO2; 3:1, Hex:EtOAc) to afford acetamide 8a (0.12 g, 0.35 mmol, 64%). 1H NMR (400 MHz, CDCl3) δ 7.50-7.38 (m, 8H), 7.38-7.30 (m, 2H), 7.23 (d, J=8.4 Hz, 1H), 7.01-6.95 (dd, J=8.4, 2.7 Hz, 1H), 6.93 (d, J=2.7 Hz, 1H), 5.71 (br s, NH), 5.08 (s, 2H), 3.42-3.16 (q, J=7.0 Hz, 2H), 2.89-2.64 (t, J=7.2 Hz, 2H), 1.85 (s, 3H); 13C NMR (100 MHz, CDCl3) δ 170.2, 157.2, 143.4, 141.4, 137.0, 130.8, 129.1, 128.7, 128.6, 128.4, 128.0, 127.6, 127.2, 116.6, 114.2, 70.1, 40.7, 31.9, 23.2; HRMS m/z: [M+K+] for C23H23NO2K calcd, 384.1361. found, 384.1359.

Provenance & Evidence