3-Phenylbenzo[b]thiophene-2-carbaldehyde → 1-(3-Phenylbenzo[b]thiophen-2-yl)ethanol

Reaction equation

[C:1]1([C:7]2[C:8]3[CH:17]=[CH:16][CH:15]=[CH:14][C:9]=3[S:10][C:11]=2[CH:12]=[O:13])[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.[CH3:18][Mg+].[Br-]>C1COCC1.C(OCC)C>[C:1]1([C:7]2[C:8]3[CH:17]=[CH:16][CH:15]=[CH:14][C:9]=3[S:10][C:11]=2[CH:12]([OH:13])[CH3:18])[CH:2]=[CH:3][CH:4]=[CH:5][CH:6]=1

Participants

Procedure

To a solution of 3-phenylbenzo[b]thiophene-2-carbaldehyde (430 mg, 1.87 mmol) in THF (10 mL) cooled to −78° C. and under a nitrogen atmosphere was added 3.0M MeMgBr in diethyl ether (1.24 mL) and stirring was continued for 30 min. The reaction mixture was quenched with a saturated solution of NH4Cl (20 mL) and slowly warmed to RT. The mixture was extracted with EtOAc (×2) and the combined organic layers were washed with water, then dried (Na2SO4) and concentrated in vacuo affording 1-(3-phenylbenzo[b]thiophen-2-yl)ethanol as a white solid (472 mg, quantitative). 1H NMR (CDCl3, 400 MHz): δ 7.88-7.84 (1H, m), 7.52-7.28 (8H, m), 5.21 (1H, q, J=6.35 Hz), 2.03 (1H, s), 1.59 (3H, d, J=6.63 Hz).