反应详情

tert-Butyl 4-(((5-bromo-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-indazol-7-yl)methoxy)methyl)-4-phenylpiperidine-1-carboxylate (55 mg, 0.09 mmol) was dissolved in dry tetrahydrofuran (1.5 mL) and stirred at room temperature for 15 min. The stirred mixture was cooled to −78° C. and treated with a solution of tert-butyllithium (1.7M in pentane, 103 μL, 0.17 mmol) over several minutes. The mixture was stirred at −78° C. for 20 min, quenched by addition of a few drops of methanol and concentrated. Flash chromatography on silica gel (20% ethyl acetate/hexanes) afforded 34 mg (91%) as a clear oil. 1H-NMR (CDCl3, 300 MHz) δ 7.93 (s, 1H), 7.66 (dd, J=7.0, 1.1 Hz, 1H), 7.04-7.23 (m, 7H), 5.38 (s, 2H), 4.70 (s, 2H), 3.39 (s, 2H), 3.35-3.41 (m, 2H), 2.94-3.03 (m, 2H), 2.05-2.09 (m, 2H), 1.71-1.80 (m, 2H), 1.39 (s, 9H), 0.72-0.78 (m, 2H), 0.14 (s, 9H). Mass spec.: 552.15 (MH)+.

1. temperatureThe stirred mixture was cooled to −78° C.
2. stirringThe mixture was stirred at −78° C. for 20 min
3. customquenched by addition of a few drops of methanol
4. concentrationconcentrated
5. customFlash chromatography on silica gel (20% ethyl acetate/hexanes) afforded 34 mg (91%) as a clear oil