1-Bromopropane → HCID 10725518, compound

Participants

Reaction Conditions

Reaction Steps

3-Amino-4-pyrazolecarbonitrile 1 (Acros, 3.24 g, 30.0 mmol), propylbromide (Acros, 4.43 g, 36 mmol) and anhydrous potassium carbonate (Fisher, 5.0 g, 36 mmol) were suspended in 20 mL anhydrous DMF and heated at 80° C. in a sealed tube under argon overnight. The reaction was permitted to cool and the DMF was removed on a rotary evaporator. Water was added (100 mL) and the organics were extracted with dichloromethane (3×100 mL). The combined dichloromethane fractions were washed with water (50 mL) and brine (50 mL) and were dried (magnesium sulfate). Concentration of the organics afforded an oil which was subjected to flash chromatography on silica gel (1-3% methanol/dichloromethane). Two white crystals were obtained: compound 101 (1.88 g, 42%) elutes first and compound 102 (711 mg, 16%) elutes second. Compound 101: mp 85-90° C.; MS (ES+ calculated: 150.18; found: 151.15 M+H). HPLC (99%) purity, retention time 5.8 minutes—Method A); 1H NMR (400 MHz, DMSO-d6) δ 8.07 (s, 1H), 5.52 (s, 2H), 3.82 (t, J=7, 2H), 1.70 (m, 2H), 0.79 (t, J=7, 3H). Compound 102: mp 162-164° C.; MS (ES+ calculated: 150.18; found: 151.18 M+H). HPLC (95%) purity, retention time 6.4 minutes—Method A); 1H 1H NMR (400 MHz, DMSO-d6) δ 7.51 (s, 1H), 6.53 (s, 2H), 3.82 (t, J=7, 2H), 2.95 (m, 2H), 0.81 (t, J=7, 3H).

Provenance & Evidence