Ethylenediamine → 2-(1-benzyl-6-chloro-1H-indazol-3-yl)-N-isopropyl-5H-pyrrolo[2,3-b]pyrazine-7-carboxamide

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Reaction Steps

2-(1-Benzyl-6-chloro-1H-indazol-3-yl)-N-isopropyl-5-((2-(trimethylsilyl)ethoxy)methyl)-5H-pyrrolo[2,3-b]pyrazine-7-carboxamide (87 mg, 151 μmol) was dissolved in dichloromethane (25 mL) and to this was added trifluoroacetic acid (1.72 g, 1.17 mL, 15.1 mmol). The mixture was stirred for 4 h then concentrated in vacuo. The residue was diluted in dichloromethane and re-concentrated again, then suspended in dichloromethane and ethylenediamine (682 mg, 0.766 mL, 11.3 mmol) added. The mixture was stirred for 15 h then concentrated in vacuo. The residue was triturated with water and the solid collected by filtration and dried. The solid was adsorbed onto silica gel and purified by chromatography (silica, SiliCycle 25 g cartridge, 0-5% methanol in dichloromethane, 15 min gradient) to give 2-(1-benzyl-6-chloro-1H-indazol-3-yl)-N-isopropyl-5H-pyrrolo[2,3-b]pyrazine-7-carboxamide (78 mg, 175 μmol, quantitative) as a pale yellow powder. MS (M−H)−=443; 1H NMR (DMSO-d6) δ: 12.84 (br. s., 1H), 9.05-9.13 (m, 1H), 8.37-8.50 (m, 2H), 8.08 (d, J=1.1 Hz, 1H), 8.01 (d, J=7.6 Hz, 1H), 7.23-7.38 (m, 6H), 5.79 (s, 2H), 4.20 (dq, J=13.6, 6.7 Hz, 1H), 1.30 (d, J=6.4 Hz, 6H).

Provenance & Evidence