Pyridine, hydrofluoride (1:1) → HCID 59001066, compound

Participants

Reaction Steps

Hydrogen fluorideepyridine (10 mL) was added to a 0° C. solution of ethyl 2-(4-chloro-benzenesulfonylamino)-4-methyl-4-pentenoate (1.0 g, 3.0 mmol) in THF (15 mL). The reaction mixture was allowed to warm to rt. After 5 h, an additional portion (10 mL) of hydrogen fluoride-pyridine was added. The mixture was stirred for 24 h, then a third portion of hydrogen fluoride-pyridine (10 mL) was added. After a total of 53 h, the reaction was quenched with ice chips (20 mL). The crude mixture was poured into ice water (500 mL) and extracted with CH2Cl2 (2×200 mL). The combined organic layers were washed with sat. aq. NaHCO3 (100 mL) and concentrated in vacuo. The crude concentrate was purified using silica gel column chromatography (10:1 to 5:1 gradient, hexanes/EtOAc) to afford 0.395 g (37% yield) of ethyl 2-(4-chlorobenzenesulfonylamino)-4-fluoro-4-methyl-pentanoate and 0.425 g (46% yield) of 4-chloro-N-(5,5-dimethyl-2-oxo-tetrahydro-furan-3-y)-benzenesulfonamide. Data for ethyl 2-(4-chlorobenzenesulfonylamino)-4-fluoro-4-methyl-pentanoate: LCMS (M+Na)+374.1; 1H NMR (500 MHz, CDCl3) 7.78 (d, 2H, J=8.9), 7.47 (d, 2H, J=8.5), 5.19 (d, 1H, J=7.9), 4.08 (m, 1H), 3.93 (m, 2H), 2.09-1.94 (m, 2H), 1.42 (d, 3H, J=21.6), 1.37 (d, 3H, J=21.6), 1.12 (t, 3H, J=7.0). Data for 4-chloro-N-(5, 5-dimethyl-2-oxo-tetrahydro-furan-3-y)-benzenesulfonamide: LCMS (M+Na)+326.0; 1H NMR (400 MHz, DMSO-d6) 8.41 (d, 1H, J=9.1), 7.86 (d, 2H, J=8.6), 7.67 (d, 2H, J=8.8), 4.57 (m, 1H), 2.22 (dd, 1H, J=12.4, 9.0), 1.72 (t, 1H, J=12.0), 1.33 (s, 3H), 1.31 (s, 3H).

Provenance & Evidence