m-Chloroperbenzoic acid → HCID 178465310, compound

Participants

Reaction Steps

To 1-ethyl-3-[6-fluoro-5-[2-(1-hydroxy-1-methyl-ethyl)pyrimidin-5-yl]-7-[(2R)-tetrahydrofuran-2-yl]-1H-benzimidazol-2-yl]urea (23) (10.24 g, 23.66 mmol) in a 1 L round bottom flask under N2 at 23° C. was added DMF (200 mL) followed by a solution of tetrazole (105.2 mL of 0.45 M in MeCN, 47.32 mmol) followed by N-dibenzyloxyphosphanyl-N-isopropyl-propan-2-amine (12.26 g, 11.93 mL, 35.49 mmol). After 4.5 h more N-dibenzyloxyphosphanyl-N-isopropyl-propan-2-amine (4 mL) was added. After stirring a further 16 h the reaction was cooled to 0° C. (ice-water bath) then treated with mCPBA (15.17 g, 61.52 mmol). The mixture was stirred at 0° C. for 30 min then at 23° C. for 30 min after which the reaction mixture was partitioned between water (400 mL) and EtOAc (700 mL). The organic layer was separated, washed with saturated aqueous sodium bicarbonate (500 mL), 10% aqueous sodium bisulfate (500 mL), saturated aqueous sodium bicarbonate (500 mL), and brine (500 mL) then dried (magnesium sulfate), filtered and concentrated. The residue was purified by MPLC using an ISCO COMBIFLASH brand flash chromatography purification system (330 g column) eluting with a 0-10% EtOH in DCM linear gradient over 16.5 column volumes at a 200 mL/min flow rate. After concentration in vacuo, (R)-dibenzyl 2-(5-(2-(3-ethylureido)-6-fluoro-7-(tetrahydrofuran-2-yl)-1H-benzo[d]imidazol-5-yl)pyrimidin-2-yl)propan-2-ylphosphate (24) (13.89 g, 20.17 mmol, 85.27%) was obtained as a white solid. ESMS (M+1)=689.5; 1H NMR (300 MHz, CD3OD) δ8.88 (d, J=1.6 Hz, 2H), 7.37 (d, J=6 Hz, 1H), 7.30 (m, 10H), 5.38-5.33 (m, 1H), 5.12-5.01 (m, 4H), 4.24 (dd, J=6.8, 14.9 Hz, 1H), 3.98 (dd, J=6.9, 15.1 Hz, 1H), 3.35-3.27 (m, 3H), 2.52 (q, J=5.9 Hz, 1H), 2.14-2.05 (m, 2H), 1.91 (s, 6H) and 1.22-1.14 (m, 3H) ppm.

Provenance & Evidence