Acetic Acid → 1-(3-Hydroxy-5,6,7,8-tetrahydronaphthalen-2-yl)ethan-1-one

Participants

Reaction Steps

To 5,6,7,8-tetrahydro-2-naphthol 14 (10 mmol, 1.48 g) placed in a flask flushed with argon at room temperature, was slowly added TiCl4 (11 mmol, 1.2 mL). The resulting dark cherry-colored mixture was stirred at room temperature, and when gas evolution ceased, 15 mmol (1.07 mL) of acetic acid was added to the solid. The resulting thick solution was stirred at room temperature for 15 min, then brought to 120° C. and left to stir at this temperature for an additional hour. The reaction mixture was then cooled to room temperature, diluted with CH2Cl2 (30 mL) and quenched with H2O (30 mL). A cloudy solution was obtained which was easily extracted with CH2Cl2. The organic layer was washed with H2O (2×30 mL), dried (Na2SO4), and concentrated under reduced pressure. The crude material was purified by silica gel column chromatography using a mixture of hexanes/EtOAc (95/5) to give 15 as a yellowish solid (1.14 g, 59% yield). mp 70-72° C.; 1H NMR (CDCl3) δ 1.77 (m, 4H), 2.59 (s, 3H), 2.76 (m, 4H), 6.68 (s, 1H), 7.41 (s, 1H), 11.96 (s, 1H); 13C NMR (CDCl3) δ 22.87, 23.42, 26,72, 28.82, 30.17, 117.82, 118.21, 128.10, 131.04, 147.71, 160.09, 204.16; IR (KBr, v cm−1) 2934, 1621, 1491, 1344; MS (ESI) 191 (M+1). Anal. Calcd for C12H14O2: C, 75.76; H, 7.42. Found: C, 75.91; H, 7.46.

Provenance & Evidence