反应详情

Part C: 1-(2-(N-Boc-aminomethyl)phenyl)-3-trifluoromethylpyrazol-5-yl-carboxylic acid: To a solution of 1-(2-cyanophenyl)-5-furyl-3-trifluoromethylpyrazole (1.5 g, 4.67 mmol) in DMF (20 mL) was portion by portion added NaBH4 (0.71 g, 18.7 mmol) and then CoCl2 (0.61 g, 4,67 mmol) at 0° C. After the resulting mixture was stirred at room temperature for 18 hours, a black suspension was cooled to 0° C. and carefully acidified with 6N HCl (20 mL). The resulting mixture was stirred at room temperature for 3 hours, and neutralized with 1N NaOH to pH 14. The mixture was diluted with EtOAc (100 mL), and filtered through a pad of sand (top layer) and Celite (bottom layer). The filtrate was separated and the organic layer was washed with brine (5×10 mL), dried over Na2SO4, and concentrated to give 1-(2-(aminomethyl)phenyl)-5-furyl-3-trifluoromethylpyrazole (1.4 g, 91.5%). 1H NMR (CD3OD) δ7.69-7.61 (m, 2H), 7.52 (d, J=1.5 Hz, 1H), 7 47 (td, J=7.7 Hz, J=1.1 Hz, 1H), 7.34 (d, J=8.0 Hz, 1H), 7.07 (s, 1H), 6.34 (dd, J=1.8 Hz, J=3.6 Hz, 1H), 5.75 (d, J=3.3 Hz, 1H), 3.40 (s, 2H); ESMS(+): 308 (M+H, 100);

1. customat 0° C
2. temperaturea black suspension was cooled to 0° C.
3. stirringThe resulting mixture was stirred at room temperature for 3 hours
4. filtrationfiltered through a pad of sand (top layer) and Celite (bottom layer)
5. customThe filtrate was separated
6. washthe organic layer was washed with brine (5×10 mL)
7. dry with materialdried over Na2SO4
8. concentrationconcentrated