Diisopropylethylamine → Tert-butyl 4-(5-(3,5-dimethylisoxazol-4-yl)-2-oxo-3-phenylindolin-3-yl)piperazine-1-carboxylate

Participants

Reaction Steps

676 mg (2.0 mmol) of 3-chloro-5-(3,5-dimethylisoxazol-4-yl)-3-phenylindolin-2-one and 774 mg (6.0 mmol) of DIPEA were dissolved in 20 ml of THF, after the addition of 774 mg (4.0 mmol) of tert-butyl piperazine-1-carboxylate, the reaction solution was stirred for 0.5 h at room temperature. Subsequently, the solution was diluted with water. The aqueous phase was extracted with CH2Cl2 (2×30 mL). The combined organic phases were washed with aqueous NaHCO3 and with water, dried and concentrated in vacuum. The resulting residue was purified by chromatography (eluent: CH2Cl2/MeOH=20/1) to give product (940 mg, 96%) as a white solid. 1H NMR (400 MHz, DMSO-d6): δH 10.75 (s, 1H), 7.51 (d, J=8.0 Hz, 1H), 7.25-7.38 (m, 6H), 6.98 (d, J=8.0 Hz, 1H), 3.27-3.29 (m, 4H), 2.47-2.38 (m, 4H), 2.36 (s, 3H), 2.18 (s, 3H), 1.35 (s, 9H). MS (ESI) m/e [M+1]+ 489.

Provenance & Evidence