反应详情

In a Parr shaker bottle was placed 1-(2-methoxy-2-methyl-propyl)-3-nitro-1H-pyrazole (1.33 g, 6.68 mmol), 10% palladium on activated carbon (135 mg) and ethanol (50 mL). The bottle was then placed on the Parr shaker at 50 psi of hydrogen pressure for 2 h. The reaction was then filtered through a pad of celite and washed with ethanol and concentration in vacuo with silica gel (3 g) and purified on Biotage Flash chromatography system (40S column, silica gel, 5% methanol/ethyl acetate) to afford 1-(2-methoxy-2-methyl-propyl)-1H-pyrazol-3-ylamine (802 mg, 71%) as a colorless oil: ES-HRMS m/e calcd for C23H33N3O5S (M+H)+ 464.2214, observed 464.2208; 1H NMR (300 MHz, DMSO-d6) δ ppm 1.04 (s, 6H, 2×CH3), 3.13 (s, 3H, OCH3), 3.80 (s, 2H, NCH2), 4.48 (brs, 2H, NH2), 5.38 (d, J=2.3 Hz, 1H, Ar), 7.21 (d, J=2.3 Hz, 1H, Ar).

1. filtrationThe reaction was then filtered through a pad of celite
2. washwashed with ethanol and concentration in vacuo with silica gel (3 g)
3. custompurified on Biotage Flash chromatography system (40S column, silica gel, 5% methanol/ethyl acetate)