Dimethylformamide → HCID 52952053, compound

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Reaction Steps

To a stirred suspension of compound 27 (6.00 g, 42.5 mmol) in anhydrous dichloromethane (200 mL) were successively added, under argon, anhydrous N,N-dimethylformamide (2 mL) and thionyl chloride (12.4 mL, 0.17 mol). The mixture was refluxed for 3 h. After cooling to room temperature, the solvent was evaporated under reduce pressure and the residue was dissolved in anhydrous toluene (40 mL). The solvent was evaporated under vacuum and the residue was dissolved in anhydrous tetrahydrofuran (40 mL). A solution of diethylamine (8.79 mL, 85.0 mmol) in anhydrous tetrahydrofuran (10 mL) was added dropwise, at 0° C. The mixture was then stirred at room temperature for 12 h. The solvent was evaporated under reduce pressure and the residue was dissolved in water (80 mL) before addition of a 5% aqueous sodium carbonate solution (10 mL). The mixture was extracted with dichloromethane (4×80 mL). The organic layers were combined, dried on magnesium sulfate, filtered and evaporated under vacuum. The residue was chromatographed (Al2O3, AcOEt) to give compound 86 (5.66 g, 28.8 mmol) as a yellow liquid. Yield 68%; Rf (Al2O3, AcOEt) 0.78; IR (CCl4) ν 1298, 1401, 1433, 1562, 1612, 1647, 2936, 2978 cm−1: 1H NMR (200 MHz, CDCl3) δ 1.00 (t, 3H, J=7.1 Hz), 1.12 (t, 3H, J=7.1 Hz), 3.09 (q, 2H, J=7.1 Hz), 3.42 (q, 2H, J=7.1 Hz), 6.80 (m, 1H), 7.05 (ddd, 1H, 5JH-F=1.9 Hz, J=1.3, 5.1 Hz), 8.15 (d, 1H, J=5.1 Hz); MS m/z 196 (M+, 22), 195 (26), 124(100), 96 (36), 76 (11), 69 (12).

Provenance & Evidence