Tetrabutylammonium Fluoride → 2-(6-fluoro-1-methyl-1H-indazol-3-yl)-5H-pyrrolo[2,3-b]pyrazine-7-carboxylic acid [(R)-1-(4,5-dihydro-oxazol-2-yl)-ethyl]-amide

Participants

Reaction Conditions

Reaction Steps

In a small vial, 2-(6-fluoro-1-methyl-1H-indazol-3-yl)-5-(2-trimethylsilanylethoxymethyl)-5H-pyrrolo[2,3-b]pyrazine-7-carboxylic acid [(R)-1-(4,5-dihydro-oxazol-2-yl)-ethyl]-amide (85 mg, 0.16 mmol) was dissolved in tetrabutylammonium fluoride (1.0 M in THF, 1.6 ml, 1.6 mmol). The yellow reaction mixture was stirred at 60° C. overnight then cooled to room temperature, quenched with water and extracted with EtOAc (2×). The combined organic layers were washed with water and brine then dried over sodium sulfate, filtered and concentrated. The residue was chromatographed over silica gel with MeOH/CH2Cl2/0.5% NH4OH (gradient 0-5% MeOH) to afford 27 mg (40%) of 2-(6-fluoro-1-methyl-1H-indazol-3-yl)-5H-pyrrolo[2,3-b]pyrazine-7-carboxylic acid [(R)-1-(4,5-dihydro-oxazol-2-yl)-ethyl]-amide as an off-white solid. MS: (M+Na)+=430; 1H NMR (DMSO-d6, 300 MHz): δ (ppm) 12.93 (br. s., 1H), 9.14 (s, 1H), 8.69 (dd, J=9.1, 5.3 Hz, 1H), 8.57 (d, J=8.3 Hz, 1H), 8.49 (s, 1H), 7.69 (dd, J=9.8, 1.9 Hz, 1H), 7.14 (td, J=9.1, 2.3 Hz, 1H), 4.97 (quin, J=7.5 Hz, 1H), 4.27-4.39 (m, 2H), 4.16 (s, 3H), 3.79 (td, J=9.3, 4.3 Hz, 2H), 1.50 (d, J=7.2 Hz, 3H).

Provenance & Evidence