Diethyl Ether → 4,5,6,7-Tetrahydrobenzo[b]thiophene-3-carboxaldehyde

Participants

Reaction Steps

A solution of 4,5,6,7-tetrahydro-1-benzothien-3-ylmethanol (Step 1, 320 mg, 1.9 mmol) in dichloromethane (10 mL) was added to a stirred solution of 1,1,1-tris(acetyloxy)-1,1-dihydro-1,2-benziodoxol-3-(1H)-one (0.92 g, 2.1 mmol) in dichloromethane (10 mL) under nitrogen and stirred at room temperature for 20 minutes. Diethyl ether (50 mL) and 1N sodium hydroxide solution (25 mL) were added and the mixture stirred vigorously for 15 minutes. The organic layer was washed with sodium hydroxide, water and brine, dried over MgSO4 and evaporated in vacuo to give 4,5,6,7-tetrahydro-1-benzothiophene-3-carbaldehyde (280 mg, 88%). 1H NMR (360 MHz, CDCl3) δ 9.88 (1H, s), 7.85 (1H, s), 2.92–2.88 (2H, m), 2.76 (2H, t, J=6.0 Hz), 1.88–1.76 (4H, m).

Provenance & Evidence