反应详情

A mixture of 5-hydrazinyl-2-methylpyridine hydrochloride (5.0 g, 31 mmol) and 4,4,4-trifluoro-3-oxo-butyronitrile (9.0 g, 65 mmol) in ethanol (50 mL) was treated with cone HCl (5.0 mL, 60 mmol) and the resultant mixture was heated to reflux overnight. The solvent was removed in vacuo and the residue was dissolved in EtOAc and neutralized with saturated Na2CO3 solution. The organic layer was dried (Na2SO4), concentrated in vacuo and purified by pre-HPLC to give 2-(6-methyl-pyridin-3-yl)-5-trifluoromethyl-2H-pyrazol-3-ylamine (1.3 g, 10% yield over 2 steps). 1HNMR (400 MHz, CDCl3) δ 9.17 (d, J=1.6 Hz, 1 H), 8.40 (dd, J=8.4, 2.4 Hz, 1 H), 7.62 (d, J=8.4 Hz, 1 H), 5.97 (s, 1 H), 2.80 (s, 3 H); MS (ESI) m/z: 243.2 (M+H+).

1. temperatureto reflux overnight
2. customThe solvent was removed in vacuo
3. dissolutionthe residue was dissolved in EtOAc and neutralized with saturated Na2CO3 solution
4. dry with materialThe organic layer was dried (Na2SO4)
5. concentrationconcentrated in vacuo
6. custompurified by pre-HPLC