反应详情

3-Methoxy-5-nitroindazole-1-carboxylic acid tert-butyl ester (0.33 g, 1.11 mmol) and palladium (10% wt) on carbon (0.24 g, 20% wt) were dissolved in EtOAc (25 mL). The flask was evacuated and filled with N2 (×5), then evacuated and filled with hydrogen (×10) and left over a weekend. The mixture was filtered over celite and the solvents removed in vacuo. Purification by column chromatography on silica gel (Jones, 20 g) loading in DCM and eluting in 5:1 Hexanes:EtOAc stepwise to 7:3 Hexanes:EtOAc yielded the title compound as a white powder. 1H NMR (400 MHz, CDCl3): δ=1.69 (s, 9H), 3.73 (brs, 2H), 4.15 (s, 3H), 6.85 (d, J=2.0 Hz, 1H), 6.91 (dd, J=8.8, 2.4 Hz, 1H), 7.74 (brs, 1H). MS (ES+): m/z 164.3 (65) [MH+](fragment ion, loss of Boc group).

1. customThe flask was evacuated
2. additionfilled with N2 (×5)
3. customevacuated
4. additionfilled with hydrogen (×10)
5. waitleft over a weekend
6. filtrationThe mixture was filtered over celite
7. customthe solvents removed in vacuo
8. customPurification by column chromatography on silica gel (Jones, 20 g) loading in DCM
9. washeluting in 5:1 Hexanes