Sodium borohydride → 2-Cyclopentyl-1-[2-(6-methoxy-2-naphthyl)-1-benzofuran-3-yl]-1-ethanol
Reaction equation
[CH:1]1([CH2:6][C:7]([C:9]2[C:13]3[CH:14]=[CH:15][CH:16]=[CH:17][C:12]=3[O:11][C:10]=2[C:18]2[CH:27]=[CH:26][C:25]3[C:20](=[CH:21][CH:22]=[C:23]([O:28][CH3:29])[CH:24]=3)[CH:19]=2)=[O:8])[CH2:5][CH2:4][CH2:3][CH2:2]1.[BH4-].[Na+]>C(O)C>[CH:1]1([CH2:6][CH:7]([C:9]2[C:13]3[CH:14]=[CH:15][CH:16]=[CH:17][C:12]=3[O:11][C:10]=2[C:18]2[CH:27]=[CH:26][C:25]3[C:20](=[CH:21][CH:22]=[C:23]([O:28][CH3:29])[CH:24]=3)[CH:19]=2)[OH:8])[CH2:5][CH2:4][CH2:3][CH2:2]1Participants
4
Procedure
To a mixture of 2-cyclopentyl-1-[2-(6-methoxy-2-naphthyl)-1-benzofuran-3-yl]-1-ethanone (2.03 g, 5.28 mmol) in ethanol (25 mL) cooled in an ice bath was added sodium borohydride (1.05 g, 27.7 mmol) in three portions. The reaction mixture was stirred for about 18 hours at room temperature and then concentrated. The residue was partitioned in warm ethyl acetate and water. The organic phase was washed with water and brine. It was dried over anhydrous magnesium sulfate, filtered and concentrated to afford 2-cyclopentyl-1-[2-(6-methoxy-2-naphthyl)-1-benzofuran-3-yl]-1-ethanol as a cream-colored solid (1.84 g), mp 176-177° C. 1HNMR (200 MHz, DMSO-d6): δ8.2 (s, 1H), 7.8-8.0 (m, 4H), 7.6 (d, 1H, J=7.5 Hz), 7.2-7.45 (m, 4H), 5.4 (s, 1H), 5.1-5.2 (br, 1H), 3.9 (s, 3H), 1.95-2.15 (br m, 1H), 1.8-1.95 (br m, 2H), 1.2-1.6 (br m, 4H), and 1.0-1.2 ppm (br m, 2H).