Water → 3-(5-chloro-2-methoxyphenyl)-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-pyrazol-4-amine

Participants

Reaction Conditions

Reaction Steps

To a solution of 3-(5-chloro-2-methoxyphenyl)-4-nitro-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-pyrazole (5.97 g, 15.6 mmol) in 25 mL ethanol was added 50 mL water, ammonium chloride (3.37 g, 62.9 mmol), and iron powder (4.367 g, 78.2 mmol). The reaction mixture was stirred at 75° C. for 1.5 hours. After cooling to room temperature, the reaction was diluted with dichloromethane and filtered through a celite pad, rinsing with more dichloromethane. The filtrate was added to 150 mL saturated aqueous sodium bicarbonate and extracted twice with dichloromethane. The combined organic extracts were dried over magnesium sulfate and concentrated to yield 5.50 g (100%) of 3-(5-chloro-2-methoxyphenyl)-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-pyrazol-4-amine, which was carried forward without purification. LCMS (ESI) m+H=354.3; 1H NMR (400 MHz, CDCl3) δ: 7.44 (d, 1H), 7.34 (d of d, 1H), 7.28 (s, 1H), 6.92 (d, 1H), 5.24 (s, 2H), 3.52 (t, 2H), 0.85 (t, 2H), −0.04 (s, 9H).

Provenance & Evidence