Cesium carbonate → (S)-4-(Benzyloxy)-1-(1-(2-(3-fluoropyrrolidin-1-yl)ethyl)-1H-indazol-5-yl)pyridin-2(1H)-one

Participants

Reaction Steps

To a solution of 4-(benzyloxy)-1-(1H-indazol-5-yl)pyridin-2(1H)-one (0.51 g, 1.6 mmol) in DMSO (5.0 mL) was added (S)-1-(2-chloroethyl)-3-fluoropyrrolidine (0.24 g, 1.6 mmol) and Cs2CO3 (3.1 g, 9.5 mmol). The reaction mixture was stirred at ambient temperature for 18 h, and then the reaction mixture was diluted with H2O (10 mL) and extracted with EtOAc (4×20 mL). The organic extracts were washed with brine (3×20 mL) and dried (Na2SO4). Purification by flash chromatography (silica gel, CH2Cl2/80:18:2 CH2Cl2/MeOH/NH4OH, 100.0 to 0:100), followed by additional flash column chromatography (silica gel, CH2Cl2/10% MeOH in CH2Cl2, 100:0 to 10:90), followed by treatment with activated charcoal, followed by final purification by preparative HPLC (Phenomenex Luna C18 (2), 250.0×21.2 mm, 10 micron, H2O with 0.05% TFA and CH3CN with 0.05% TFA) gave the title compound (58.3 mg, 8%) as a white powder: 1H NMR (500 MHz, CDCl3) δ 8.04 (s, 1H), 7.67 (d, J=1.5 Hz, 1H), 7.55 (d, J=9 Hz, 1H), 7.45-7.37 (m, 6H), 7.31-7.30 (m, 1H), 6.12-6.10 (m, 2H), 5.16 (dt, J=55.5, 4.5 Hz, 1H), 5.07 (s, 2H), 4.58 (t, J=7.0 Hz, 2H), 3.01 (br m, 2H), 2.97-2.93 (m, 2H) 2.92-2.90 (m, 1H), 2.56 (br s, 1H), 2.17-2.03 (m, 2H); ESI MS m/z 433 [M+H]+; HPLC (Method A)>99% (AUC), tR=13.9 min.

Provenance & Evidence