2-Methoxyethanol → 3-[5-amino-4-(3-[1,3]dioxolan-2-yl-benzoyl)-pyrazol-1-yl]-N-cyclopropyl-4-methyl-benzamide

Participants

Reaction Steps

Dry sodium hydride (21 mg, 0.84 mmol) was added to a solution of 2-methoxyethanol (0.63 ml, 8.0 mmol) in dioxane (2 ml) at 0° C. The mixture was stirred at room temperature for 30 min. 2-Benzoyl-3,3-bis-methylsulfanyl-acrylonitrile 2 (0.20 g, 0.80 mmol) was added, and the mixture was stirred at 85° C. for 4 h. The mixture was cooled to room temperature. N-Cyclopropyl-3-hydrazino-4-methyl-benzamide trifluoroacetic acid salt (0.26 g, 0.80 mmol), followed by diisopropylethylamine (0.14 ml, 0.80 mmol), was added and the reaction was heated to 85° C. for another 11 h. Solvents were removed in vacuo. The residue was diluted in saturated NaHCO3 solution and was extracted three times with EtOAc. Combined organic layers were dried over MgSO4, filtered and concentrated. The crude product was purified by flash chromatography (SiO2, gradient of 70 to 90% EtOAc/hexanes). The product was further purified by washing with a warm mixture of EtOAc and hexanes to give the desired 3-[5-amino-4-benzoyl-3-(2-methoxy-ethoxy)-pyrazol-1-yl]-N-cyclopropyl-4-methyl-benzamide 5 as a white solid (60 mg, 17%). HPLC (4 minute 10-90 gradient) tR 2.17 min; MS m/z 435.2 [M+H]+; 1H NMR (DMSO-d6, 500 MHz) δ 8.47 (s, 1 H), 7.89 (d, J=7.9, 1 H), 7.83 (s, 1 H), 7.64 (d, J=7.4, 2 H), 7.49 (d, J=7.7, 2 H), 7.40-7.43 (m, 2 H), 6.99 (bs, 2 H), 4.12 (m, 2 H), 3.42 (m, 2 H), 3.12 (s, 3 H), 2.86 (m, 1 H), 2.07 (s, 3 H), 0.69 (m, 2 H), 0.56 (m, 2 H) ppm.

Provenance & Evidence