Tetrabutylammonium Fluoride → 2-(6-Fluoro-1-methyl-1H-indazol-3-yl)-5H-pyrrolo[2,3-b]pyrazine-7-carboxylic acid ((R)-1-cyanomethyl-pyrrolidin-3-yl)-amide

Participants

Reaction Conditions

Reaction Steps

To a 100 ml round-bottomed flask containing 2-(6-fluoro-1-methyl-1H-indazol-3-yl)-5-(2-trimethylsilanyl-ethoxymethyl)-5H-pyrrolo[2,3-b]pyrazine-7-carboxylic acid ((R)-1-cyanomethyl-pyrrolidin-3-yl)-amide (216 mg, 0.394 mmol) suspended in THF (5 ml) was added TBAF (1.0 M in THF, 5.0 ml, 5.0 mmol). The vial was backfilled with nitrogen then sealed and heated in an oil bath at 85° C. for 2 h. The reaction was cooled to room temperature, quenched with acetone (5 ml) and sat'd NaHCO3 (10 ml). The mixture was stirred for 1 h then diluted with water and extracted with EtOAc. Brine was added and the aqueous layer was extracted twice with EtOAc. The combined organics were washed with water and brine then dried over MgSO4, filtered and concentrated. The crude solid was triturated with Et2O, EtOAc, and hexanes to afford 54 mg (33%) of 2-(6-Fluoro-1-methyl-1H-indazol-3-yl)-5H-pyrrolo[2,3-b]pyrazine-7-carboxylic acid ((R)-1-cyanomethyl-pyrrolidin-3-yl)-amide as a white solid. LC-MS (M+H)+=419; 1H NMR (300 MHz, DMSO-d6) δ: 12.87 (br. s., 1H), 9.10 (s, 1H), 8.39-8.52 (m, 2H), 8.31 (d, J=7.8 Hz, 1H), 7.63-7.73 (m, 1H), 7.18-7.31 (m, 1H), 4.64 (br. s., 1H), 4.14 (s, 3H), 3.81-4.05 (m, 2H), 2.97 (td, J=8.6, 4.6 Hz, 1H), 2.86 (dd, J=9.2, 6.7 Hz, 1H), 2.72 (dd, J=9.3, 3.5 Hz, 1H), 2.52-2.62 (m, 1H), 2.36-2.45 (m, 1H), 1.70-1.85 (m, 1H).

Provenance & Evidence