反应详情

温度

80 °C

To a solution of 2-(3-(3-chlorophenyl)-1-(dimethylamino)-3-oxoprop-1-en-2-yl)isoindoline-1,3-dione (2.30 g, 6.48 mmol, 1 eq) in 50 mL ethanol was added N-methylhydrazine (1.4 mL, 26 mmol, 4.0 eq). The reaction mixture was stirred at 80° C. for 2 hours and then concentrated onto silica gel. The crude mixture of regioisomers was separated and purified by flash chromatography on silica gel (0 to 80% ethyl acetate in dichloromethane) to yield: 715 mg (53%) of 3-(3-chlorophenyl)-1-methyl-1H-pyrazol-4-amine LCMS (ESI) m+H=208.2; 1H NMR (400 MHz, CDCl3) δ: 7.78 (s, 1H), 7.63 (d, 1H), 7.33 (t, 1H), 7.25 (overlapping with CDCl3, 1H), 7.04 (s, 1H), 3.84 (s, 3H), and 274.6 mg (20%) of 5-(3-chlorophenyl)-1-methyl-1H-pyrazol-4-amine. LCMS (ESI) m+H=208.2; 1H NMR (400 MHz, CDCl3) δ: 7.43 (t, 1H), 7.38 (overlapping d and s, 2H), 7.27 (d, 1H), 7.23 (s, 1H), 3.76 (s, 3H).

1. concentrationconcentrated onto silica gel
2. additionThe crude mixture of regioisomers
3. customwas separated
4. custompurified by flash chromatography on silica gel (0 to 80% ethyl acetate in dichloromethane) to yield: 715 mg (53%) of 3-(3-chlorophenyl)-1-methyl-1H-pyrazol-4-amine LCMS (ESI) m+H=208.2