Diisopropylethylamine → (2E)-2-(3-chloro-4-methylsulfonylphenyl)-2-(2-methylpropoxyimino)-N-(1-methylpyrazol-3-yl)acetamide

Participants

Reaction Steps

(E)-(3-Chloro-4-methanesulfonyl-phenyl)-isobutoxyimino-acetic acid (104 mg, 0.31 mmol), 1-methyl-1H-pyrazol-3-ylamine (30 mg, 0.31 mmol) and N,N-diisopropylethylamine (163 μL, 0.94 mmol) were combined in methylene chloride (1.5 mL) and cooled in an ice bath. O-(7-Azabenzotriazole-1-yl)-N,N,N′N′-tetramethyluronium hexafluorophosphate (119 mg, 0.31 mmol) was added and the ice bath was removed. After stirring 2 h, the reaction mixture was evaporated in vacuo. The residue was treated with saturated aqueous sodium bicarbonate solution (1 mL) and extracted with chloroform (2×3 mL). The combined organic phases were dried over sodium sulfate and evaporated in vacuo. The residue was purified by flash column chromatography (Merck silica gel 60, 40-63 μm; 50% ethyl acetate/hexanes) to afford (E)-2-(3-chloro-4-methanesulfonyl-phenyl)-2-isobutoxyimino-N-(1-methyl-1H-pyrazol-3-yl)-acetamide (122 mg, 95%) as a white solid after lyophilization from aqueous acetonitrile: LC-MS (ESI) m/e calcd for C17H21ClN4O4S [M+] 412.10, found 413 [M+H+]; H1-NMR (400 MHz, CDCl3) δ ppm 0.94 (d, J=6.7 Hz, 6 H, 2×CH3), 2.05 (m, 1 H, CH), 3.29 (s, 3 H, SO2CH3), 3.84 (s, 3 H, NCH3), 4.06 (d, J=6.8 Hz, 2 H, OCH2), 6.68 (d, J=2.3 Hz, 1 H, Ar), 7.28 (d, J=2.3 Hz, 1 H, Ar), 7.58 (dd, Jo=8.2, Jm=1.5 Hz, 1 H, Ar), 7.69 (d, Jm=1.5 Hz, 1 H, Ar), 8.19 (d, Jo=8.2 Hz, 1 H, Ar), 9.13 (brs, 1 H, NH).

Provenance & Evidence