Water → Benzo(B)Thiophene

Participants

Reaction Steps

To a well-stirred solution of 2-(4'-ethoxyphenyl)-6-ethoxybenzo[b]thiophene (0.095 g, 0.32 mmol) and 3,4,5-trimethoxybenzoyl chloride (0.159 g, 0.69 mmol) in CH2Cl2 (15 mL) was added AlCl3 (0.139 g, 1.04 mmol) portion-wise over a 5 minute period. After 30 min., water was added, and the product was isolated initially by extraction with CH2Cl2 and subsequently by extraction with EtOAc. The organic layers were separately washed with brine and then combined and dried over MgSO4. Purification by flash chromatography (silica gel, 80:20 hexane/EtOAc) afforded benzo[b]thiophene (0.110 g, 0.2 mmol, 69%) as an off-white solid. 1H-NMR (CDCl3, 360 Mhz) δ 7.65 (d, J=8.9 Hz, 1H, ArH), 7.32 (d, J=2.3 Hz, 1H, ArH), 7.29 (d, J=8.8 Hz, 2H, ArH), 7.06 (s, 2H, ArH), 7.00 (dd, J=8.9, 2.4 Hz, 1H, ArH), 6.73 (d, J=8.7 Hz, 2H, ArH), 4.12 (q, J=7.0 Hz, 2H, --CH2), 3.97 (q, J=6.9 Hz, 2H, --CH2), 3.83 (s, 3H, --OCH3), 3.73 (S, 6H, --OCH3), 1.47 (t, J=6.9 Hz, 3H, --CH3), 1.37 (t, J=7.0 Hz, 3H, --CH3).

Provenance & Evidence