Trifluoroacetic acid methylene chloride → phenyl(1H-pyrrolo[2,3-c]pyridin-2-yl)methanone O-[2-(methylamino)ethyl]oxime dihydrochloride

Participants

Reaction Steps

tert-Butyl methyl[2-[[[phenyl (1H-pyrrolo[2,3-c]pyridin-2-yl)methylene]amino]oxy]ethyl]carbamate (Example 128) (100 mg, 0.25 mmol) in trifluoroacetic acid/CH2Cl2 (2:1, 5 mL) was stirred at ambient temperature. After 5 h, the reaction mixture was concentrated under reduced pressure. The residue was diluted with CH2Cl2 (35 mL) and washed with saturated NaHCO3 (20 mL) and saturated NaCl (20 mL), dried (Na2SO4) and concentrated under reduced pressure. The residue was purified by column chromatography (silica gel, 89:10:1 CH2Cl2/MeOH/NH4OH). The obtained product was dissolved in EtOAc, an excess of 1 N HCl in Et2O was added and the mixture was concentrated under reduced pressure. The resulting solid was triturated with EtOAc and collected by vacuum filtration to give phenyl(1H-pyrrolo[2,3-c]pyridin-2-yl)methanone O-[2-(methylamino)ethyl]oxime dihydrochloride (46.8 mg, 51%) as an off-white solid (geometry of the oxime double bond undefined): 1H NMR (500 MHz, DMSO-d6) δ 2.63 (3H, s), 3.39 (2H, br s), 4.59 (2H, t, J=4.5 Hz), 6.96 (1H, s), 7.50-7.61 (5H, m), 8.14 (1H, d, J=6.3 Hz), 8.34 (1H, d, J=6.3 Hz), 9.31-9.35 (3H, m), 13.56 (1H, s), 15.28 (1H, br s); ESI MS m/z 295 [C17H18N4O+H]+; HPLC (Method A) 96.6% (AUC), tR=13.5 min.

Provenance & Evidence