[Si]([O:8][C@@H:9]([CH3:26])[CH2:10][CH2:11][N:12]1[CH:16]=[C:15]([B:17]2[O:21][C:20]([CH3:23])([CH3:22])[C:19]([CH3:25])([CH3:24])[O:18]2)[CH:14]=[N:13]1)(C(C)(C)C)(C)C.[F-].C([N+](CCCC)(CCCC)CCCC)CCC>C1COCC1>[CH3:25][C:19]1([CH3:24])[C:20]([CH3:22])([CH3:23])[O:21][B:17]([C:15]2[CH:14]=[N:13][N:12]([CH2:11][CH2:10][C@@H:9]([OH:8])[CH3:26])[CH:16]=2)[O:18]1A solution of (S)-1-(3-[(tert-butyldimethylsilyl)oxy]butyl]-4-(tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (Compound 70C, 7.7 g, 20.2 mmol) in THF (30 mL) was treated with tetrabutylammonium fluoride (30 mL, 1M solution in THF) and stirred for 24 hrs at RT under nitrogen atmosphere. Tetrahydrofuran was evaporated under reduced pressure and the residue was purified by column chromatography (SiO2, 1% methanol in dichloromethane) to give colorless gum (1 g, 20%). 1H NMR (400 MHz, CDCl3) δ 7.74 (s, 1H), 7.64 (s, 1H), 4.15-4.23 (m, 2H), 3.60-3.3.71 (m, 1H), 1.7-1.98 (m, 2H), 1.23 (s, 12H), 1.12 (s, d, 3H).
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