反应详情

Benzyl bromide (1.8 mL, 15.2 mmol) and Cs2CO3 (4.89 g, 15.0 mmol) were added to a solution of 4-hydroxy-2-hydroxymethyl-2,3-dihydro-benzofuran-6-carboxylic acid tert-butyl ester (200f) (4.0 g, 15.0 mmol) in DMF (10 mL). The reaction mixture was stirred at room temperature overnight. The mixture was quenched with H2O (60 mL) and extracted EtOAc (2×60 mL). The organic layers were washed with H2O (2×100 mL), dried over MgSO4 and concentrated. The residue was purified by flash column chromatograph eluting with 30-40% EtOAc in hexanes to give a pale yellow oil (4.43 g, 83% yield). 1H NMR (400 MHz, CDCl3) δ 7.34-7.45 (m, 5 H) 7.19 (s, 1 H) 7.09 (s, 1 H) 5.13 (s, 2 H) 4.96-5.03 (m, 1 H) 3.85 (ddd, J=12.00, 6.95, 3.28 Hz, 1 H) 3.74 (dt, J=12.13, 6.06 Hz, 1 H) 3.27 (dd, J=16.42, 9.60 Hz, 1 H) 3.01 (dd, J=16.42, 7.07 Hz, 1 H) 1.58 (s, 9 H); LCMS for C21H24O5 m/z 357.00 (M+H)+.

1. customThe mixture was quenched with H2O (60 mL)
2. extractionextracted EtOAc (2×60 mL)
3. washThe organic layers were washed with H2O (2×100 mL)
4. dry with materialdried over MgSO4
5. concentrationconcentrated
6. customThe residue was purified by flash column chromatograph
7. washeluting with 30-40% EtOAc in hexanes