反应详情

温度

0 °C

To a stirring solution of 1.10 g (4.21 mmol, 1.2 equiv) of triphenylphosphine in 15 mL of CCl4 at -5° C. is added 200 μL (3.86 mmol, 1.1 equiv) of Br2. The resulting orange-yellow suspension is stirred 10 min at 0° C., then a solution of 710 mg (3.51 mmol) of (2-Benzyl-5-methyl-2H-pyrazol-3yl) methanol, prepared as in Part C, in 5 mL of CCl4 is added over 2 min. The resulting solution is stirred 0.5 h at RT, and then poured into 25 mL NaHCO3 and extracted with Et2O (2×25 mL), dried (MgSO4), and the solvent removed in vacuo. Purification of the residue by silica gel flash column chromatography using hexane/EtOAc 5/1 as eluent afforded 576 mg of the title compound as a clear oil: 1H NMR (CDCl3, 300 MHz) δ7.32 (m, 3H), 7.19 (m, 2H), 6.16 (s, 1H), 5.42 (s, 2H), 4.32 (s, 2H), 2.31 (s, 3H); low resolution MS (FAB)m/e 265 (M+).

1. stirringThe resulting solution is stirred 0.5 h at RT
2. extractionextracted with Et2O (2×25 mL)
3. dry with materialdried (MgSO4)
4. customthe solvent removed in vacuo
5. customPurification of the residue by silica gel flash column chromatography