Cesium carbonate → 2-Acetyl-4-[2-(2,2,2-trifluoroethoxy)-3-tert-butyl-5-methylphenyl]benzo[b]thiophene

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A mixture of 211 mg (0.63 mmol) of 2-acetyl-4-(2-hydroxy-3-tert-butyl-5-methylphenyl)benzo[b]thiophene, 0.1 ml (132 mg, 0.81 mmol) of 1,1,1-trifluoro-2-bromoethane and 304 mg (0.94 mmol) of Cs2CO3 in 2.5 ml of dry DMF was heated at 60° C. in a pressure tube overnight. After cooling at room temperature, 10 mL of a 5/95 ethyl acetate/hexane solution was added and the remaining mixture was stirred for 5 minutes. The solution was filtrated through a silica plug (eluent: 5/95 ethyl acetate/hexane) and the solvents were removed under pressure. 188 mg (0.44 mmol, yield: 71%) of 2-acetyl-4-[2-(2,2,2-trifluoroethoxy)-3-tert-butyl-5-methylphenyl]benzo[b]thiophene was isolated as an oil. 1H NMR (400 MHz, CDCl3) δ 7.89 (d, J=7.9 Hz, 1H), 7.75 (s, 1H), 7.54 (t, J=7.8 Hz, 1H), 7.45 (d, J=7.9 Hz, 1H), 7.26 (d, J=1.9 Hz, 1H), 7.06 (d, J=1.9 Hz, 1H), 3.63 (m, 1H), 3.52 (m, 1H), 2.56 (s, 3H), 2.38 (s, 3H), 1.48 (s, 9H).

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