Stannous chloride dihydrate → HCID 23139522, compound

Participants

Reaction Steps

To a stirred solution of 4-bromo-5-(2-methoxy-5-nitro-phenyl)-1-methyl-3-trifluoromethyl-1H-pyrazole (0.08 g, 0.20 mmol) in EtOH (0.7 mL) was added SnCl2.2H2O (0.18 g, 0.80 mmol, 4.0 eq.) and the mixture was stirred at reflux for 2 hours followed by the removal of EtOH under vacuum. The resulting solid was dissolved in EtOAc and 1N NaOH was added until the pH was adjusted to 6. The mixture was stirred overnight and filtered through celite. The aqueous phase was extracted with EtOAc (3×50 mL). The combined organic phase was dried over anhydrous MgSO4, filtered and evaporated to give 3-(4-bromo-2-methyl-5-trifluoromethyl-2H-pyrazol-3-yl)-4-methoxy-phenylamine (0.06 g, 0.17 mmol, 99% yield after two steps) as a white solid: LCMS m/z (%)=350 (M+H79Br, 95), 352 (M+H81Br, 100). 1H NMR (400 MHz, CDCl3) δ: 6.78 (dd, J=14.0, 6.0 Hz, 1H), 6.76 (dd, J=8.0, 4.0 Hz, 1H), 6.54 (d, J=4.0 Hz, 1H), 3.67 (s, 3H), 3.66 (s, 3H) 3.36 (broad s, 2H).

Provenance & Evidence