反应详情

A solution of 1-benzyl-3-(5-methoxycarbonyl-2-furyl)-1H-indazole in THF (150 mL) was added dropwise to a suspension of CaBH4.2THF (3.9 g, 18.23 mmol) in THF (150 mL) at room temperature. The resultant mixture was heated to reflux for 15 h. The reaction mixture was allowed to cool, then poured slowly onto brine. The layers were separated and the aqueous layer was extracted three times with ether. The combined organic material was dried (MgSO4) and concentrated under reduced pressure. The crude product was chromatographed on silica (30–40% EtOAc/cyclohexane) and then recrystallised (ethanol/H2O) to give the product as fine cream needles (1.56 g, 86%): mp 112–112.5° C. (lit. mp 108–109° C.); MS (EI) M+ 304; 1H-NMR (CDCl3) 4.76 (s, 2H), 5.68 (s, 2H), 6.50 (d, 1H, J=3.3 Hz), 6.90 (d, 1H, J=3.3 Hz), 7.21–7.40 (m, 8H), 8.08 (d, 1H, J=8.5 Hz); 13C-NMR (CDCl3) 54.12, 58.53, 108.87, 110.57, 110.59, 122.25, 122.38,122.50, 127.83, 128.00(2C), 128.72, 129.68(2C), 137.14, 137.53, 141.45, 149.52, 154.88; Anal. (C19H16N2O2) C, calcd 74.98; found 74.80, H, calcd 5.30; found 5.28, N, calcd 9.20; found 9.15.

1. customat room temperature
2. temperatureto reflux for 15 h
3. temperatureto cool
4. additionpoured slowly onto brine
5. customThe layers were separated
6. extractionthe aqueous layer was extracted three times with ether
7. dry with materialThe combined organic material was dried (MgSO4)
8. concentrationconcentrated under reduced pressure
9. customThe crude product was chromatographed on silica (30–40% EtOAc/cyclohexane)
10. customrecrystallised (ethanol/H2O)