Iodine → Ethyl 1-[6-(2-hydroxy-3-iodophenyl)pyridin-2-yl]-5-(trifluoromethyl)-1H-pyrazole-4-carboxylate

Participants

Reaction Steps

To a suspension of the title compound from Example 5 Step B (4.0 g, 10.6 mmol) and silver sulfate (3.31 g, 10.6 mmol) in ethanol (20 mL) was added iodine (2.69 g, 10.6 mmol), and the resulting mixture was vigorously stirred at room temperature. After 2 h, the reaction mixture was quenched with water and sodium bisulfite solution, extracted with ethyl acetate and concentrated in vacuo. Purification by chromatography on silica gel (0 to 15% EtOAc in hexanes, then 15 to 100% EtOAc in hexanes) provided the title compound: LCMS m/z 503.7 [M+H]+; 1H NMR (500 MHz, CDCl3) δ 13.08 (s, 1 H),8.17 (s, 1 H),8.10 (t, J=8.0 Hz, 1 H),8.06 (d, J=8.0 Hz, 1 H),7.86 (dd, J=7.5, 1.5 Hz, 1 H),7.82 (dd, J=8.0, 1.5 Hz, 1 H),7.52 (d, J=7.5 Hz, 1 H),6.75 (t, J=8.0 Hz, 1 H),4.33 (q, J=7.0 Hz, 2 H),1.43 (t, J=7.0 Hz, 3 H).

Provenance & Evidence