Isopropyl iodide → 2-Hydroxymethyl-4-isopropoxy-2,3-dihydro-benzofuran-6-carboxylic acid tert-butyl ester

関与物質

反応条件

反応手順

A mixture of 2-iodopropane (0.826 mL, 8.26 mmol), 4-hydroxy-2-hydroxymethyl-2,3-dihydro-benzofuran-6-carboxylic acid tert-butyl ester (200f) (2.00 g, 7.51 mmol), and K2CO3 (1.56 g, 11.3 mmol) in DMF (20 mL) was heated to 60° C. overnight. Additional 2-iodopropane (0.9 mL) and K2CO3 (0.9 g) were added. The resulting mixture was heated to 50° C. for 4 days, then cooled to room temperature, quenched with H2O and extracted with 3×EtOAc. The organic layers were washed with 2×H2O, dried over Na2SO4, and concentrated. The residue was purified by flash column chromatography with 50-70% EtOAc in hexanes to give a yellow syrup (2.0 g, 86% yield). 1H NMR (400 MHz, CDCl3) δ 7.11 (s, 1 H) 7.03 (d, J=1.01 Hz, 1H) 4.90-5.05 (m, 1 H) 4.58-4.66 (m, 1 H) 3.81-3.88 (m, 1 H) 3.67-3.77 (m 1 H) 3.21 (dd, J=16.42, 9.60 Hz, 1 H) 2.94 (dd, J=16.42, 7.07 Hz, 1 H) 1.60 (s, 9 H) 1.32-1.34 (m, 6 H); LCMS for C17H24O5 m/z 253.00 (M-tBu+H+).

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