反应详情

In a flame dried round-bottomed flask equipped with a magnetic stir bar and under inert atmosphere (N2), a solution of 1-[5-(3-nitro-pyrazol-1-ylmethyl)-furan-2-yl]-ethanol (6.50 g, 27.40 mmol) in AcCN (269.0 mL) was treated at rt with MnO2 (15.881 g, 164.40 mmol) and the reaction mixture was stirred at rt for 16 h before being filtered through Celite. The solvent was removed under reduced pressure. Purification of the residue by FC (50:50 hept-EA) gave the title compound as a mixture with 5-(3-nitro-pyrazol-1-ylmethyl)-furan-2-carbaldehyde. TLC: rf (50:50 hept-EA)=0.20. LC-MS-conditions 02: tR=0.83 min. 1H NMR (400 MHz, CDCl3) characteristic signals δ 2.47 (s, 3H), 5.46 (s, 2H), 6.61 (d, J=3.5 Hz, 1H), 6.95 (d, J=2.3 Hz, 1H), 7.16 (d, J=3.5 Hz, 1H), 7.61 (d, J=2.3 Hz, 1H).

1. filtrationbefore being filtered through Celite
2. customThe solvent was removed under reduced pressure
3. customPurification of the residue by FC (50:50 hept-EA)