4-Methoxybenzenesulfonyl chloride → 4-Amino-5-fluoro-1-(4-methoxyphenylsulfonyl)pyrimidin-2(1H)-one

Participants

Reaction Conditions

Reaction Steps

To commercially available 4-amino-5-fluoro-pyrimidin-2-ol (1.0 grams (g), 7.75 millimoles (mmol)) in acetonitrile (CH3CN; 50 milliliters (mL)) was added bis-N,O-trimethylsilylacetamide (BSA; 5.7 mL, 23.3 mmol) and the mixture was heated at 70° C. for 1 hour (h), resulting in a clear solution. After cooling to room temperature, 4-methoxybenzene-1-sulfonyl chloride (1.8 g, 8.5 mmol) was added, and the mixture was stirred for 24 h. The solvent was evaporated and the residue was partitioned between ethyl acetate (EtOAc) and brine. The organic phase was dried over magnesium sulfate (MgSO4), filtered, and evaporated to yield the product as a pale yellow solid (1.48 g, 64%): mp 182-185° C.; 1H NMR (300 MHz, CDCl3) δ 8.40 (br s, 1H), 8.11 (d, J=5.9 Hz, 1H), 8.04-7.98 (m, 2H), 7.02-6.96 (m, 2H), 5.77 (br s, 1H), 3.88 (s, 3H); ESIMS m/z 300 ([M+H]+).

Provenance & Evidence