Tetrabutylammonium Fluoride → 1,1-Dimethylethyl {[3'-(hydroxymethyl)-5-(methyloxy)-3-biphenylyl]methyl}carbamate

To a solution of 1,1-dimethylethyl {[3′-({[(1,1-dimethylethyl)(dimethyl)silyl]oxy}methyl)-5-(methyloxy)-3-biphenylyl]methyl}carbamate (1.5 g, 3.28 mmol) in THF (20 mL) was added a solution of nBu4NF (0.94 g, 3.61 mmol) in THF (10 mL). This mixture was stirred at room temperature over night. After the solvent was removed under reduced pressure, the residue was diluted with EtOAc (30 mL). The organic layer was washed with water (10 mL×2), brine (10 mL×2), and dried over Na2SO4. The product, 1,1-dimethylethyl {[3′-(hydroxymethyl)-5-(methyloxy)-3-biphenylyl]-methyl}carbamate, (0.9 g) was purified by flash column chomatography (PE:EA=3:1). (Yield: 80%). 1H NMR (400 MHz, CDCl3) δ 1.47 (s, 9H), 3.86 (s, 3H), 4.35 (d, J=7.6 Hz, 2H), 4.76 (s, 2H), 4.89 (s, 1H), 6.83 (s, 1H), 7.02 (s, 1H), 7.09 (s, 1H), 7.34-7.58 (m, 4H); 13C NMR (100 MHz, CDCl3) δ 28.4, 44.7, 55.4, 65.2, 79.6, 111.9, 118.7, 125.8, 126.1, 126.4, 129.0, 140.9, 141.2, 141.5, 142.8, 156.0, 160.3. HPLC: retention time: 11.558 min; purity: 98.7%; MS: m/z 343 (M+).