反应详情

A solution of 2-(2-propynyloxy)tetrahydro-2H-pyran (69) (0.758 g, 5.41 mmol), CuI (17 mg, 0.09 mmol) and PdCl2(PPh3)2 (0.158 g, 0.023 mmol) in THF (15 mL) was purged with N2. 1-Iodo-4-(trifluoromethoxy)benzene (70) (1.30 g, 4.51 mmol) in THF (10 mL) was added, followed by a solution of methylhydrazine sulfate (1.95 g, 13.5 mmol) and NaHCO3 (2.27 g, 27 mmol) in water (25 mL). The mixture was flushed with carbon monoxide and then stirred at room temperature for 2 days under one atmosphere of carbon monoxide. The resulting mixture was partitioned between CH2Cl2 and water, the CH2Cl2 fraction was dried, and the solvent was evaporated. Column chromatography of the residue on silica gel (eluting with CH2Cl2) gave 1-methyl-5-[tetrahydro-2H-pyran-2-yloxy)methyl]-3-[4-(trifluoromethoxy)phenyl]-1H-pyrazole (71) (1.034 g, 64%) as a brown solid: mp 40-42° C.; 1H NMR (CDCl3) δ 7.78 (d, J=8.8 Hz, 2H), 7.21 (d, J=8.0 Hz, 2H), 6.51 (s, 1H), 4.75 (d, J=12.8 Hz, 1H), 4.69 (t, J=3.3 Hz, 1H), 4.57 (d, J=12.8 Hz, 1H), 3.94 (s, 3H), 3.84-3.91 (m, 1H), 3.53-3.60 (m, 1H), 1.68-1.88 (m, 2H), 1.50-1.66 (m, 4H). APCI MS m/z 357 [M+H]+.

1. customThe mixture was flushed with carbon monoxide
2. customThe resulting mixture was partitioned between CH2Cl2 and water
3. dry with materialthe CH2Cl2 fraction was dried
4. customthe solvent was evaporated