反应详情

To a stirred solution of compound 315 (25.5 g, 143 mmol) in DMF (120 mL) was added N-iodosuccinimide (32 g, 143 mmol) in two portions at rt. The resulting mixture was stirred at rt for 2 h. Upon workup, the mixture was poured into ice and saturated Na2CO3 aqueous solution with some sodium sulfite and extracted with ethyl acetate (2×). The combined organics were washed with saturated Na2CO3 aqueous solution (3×), dried over Na2SO4, and concentrated in vacuo. The residue was subjected to combi-flash column chromatography (methanol/DCM) to give compound 243 (39 g, 73% yield in 2 steps). 1H NMR (500 MHz, DMSO-d6) δ ppm 7.89 (1 H, s), 6.18 (2 H, s), 5.63 (1 H, d, J=7.6 Hz), 4.30 (1 H, sxt, J=7.4 Hz), 1.84-1.96 (2 H, m), 1.61-1.74 (2 H, m), 1.42-1.58 (4 H, m). LCMS-ESI (POS), M/Z, M+1: Found 305.0.

1. extractionextracted with ethyl acetate (2×)
2. washThe combined organics were washed with saturated Na2CO3 aqueous solution (3×)
3. dry with materialdried over Na2SO4
4. concentrationconcentrated in vacuo