Tetrabutylammonium Fluoride → HCID 59352744, compound

Participants

Reaction Steps

To a solution of 1′-[(2R)-tetrahydrofuran-2-ylmethyl]-6-{[tris(1-methylethyl)silyl]oxy}spiro[1-benzofuran-3,3′-indol]-2′(1H)-one (1.69 g, 3.43 mmol) in anhydrous tetrahydrofuran (15 mL) under nitrogen was added tetrabutylammonium fluoride (1 M solution in tetrahydrofuran, 10 mL, 10 mmol), and the mixture was stirred at ambient temperature for 16 h. The reaction mixture was concentrated, and the residue was re-dissolved in ethyl acetate (25 mL), washed with water (2×20 mL) and brine (20 mL), dried over sodium sulfate, filtered, and concentrated. The residue was purified by column chromatography with 40% ethyl acetate in hexanes to afford 6-hydroxy-1′-[(2R)-tetrahydrofuran-2-ylmethyl]spiro[1-benzofuran-3,3′-indol]-2′(1′H)-one (1.00 g, 86%) as a colorless solid: mp 72-74° C.; 1H NMR (300 MHz, CDCl3) δ 7.29 (ddd, J=7.5, 7.5, 1.2 Hz, 1H), 7.18-7.01 (m, 3H), 6.80-6.67 (br, 1H), 6.44 (d, J=8.4 Hz, 1H), 6.24 (d, J=2.1 Hz, 1H), 6.17-6.09 (m, 1H), 4.96-4.90 (m, 1H), 4.69-4.63 (m, 1H), 4.36-4.24 (m, 1H), 4.00-3.71 (m, 4H), 2.12-1.61 (m, 4H); MS (ES+) m/z 338.1 (M+1).

Provenance & Evidence