反应详情

A mixture of 2-butyl-4,5-dicyano-1-(4-nitrobenzyl)imidazole (2.00 g, 6.5 mmol, 1 eq), tin dichloride dihydrate (7.30 g, 32.3 mmol, 5 eq) and ethanol (13 mL) was stirred and heated at 70° for 50 minutes. The reaction was terminated by pouring the mixture onto ice and adjusting the pH to 8 with saturated aqueous NaHCO3. The aqueous mixture was extracted with ethyl acetate (3×100 mL) and the organic layers were dried (MgSO4) and concentrated to give a thick amber oil. This oil was flash chromatographed over silica gel in 75:25 to 70:30 hexane/ethyl acetate yielding 330 mg of yellow crystals; m.p. 99.0°-103.5°. NMR (200 MHz, CDCl3) δ 6.97 (d, 2H, J=10 Hz); 6.68 (d, 2H, J=10 Hz); 5.10 (s, 2H); 2.69 (t, 2H, J=7 Hz); 1.72 (t of t, 2H, J=7,7 Hz); 1.38 (t of q, 2H, J=7,7 Hz); 0.91 (t, 3H, J=7 Hz). Mass Calcd. for C16H17N5 : 279.1483. Found: 279.1489.

1. temperatureheated at 70° for 50 minutes
2. customThe reaction was terminated
3. additionby pouring the mixture onto ice
4. extractionThe aqueous mixture was extracted with ethyl acetate (3×100 mL)
5. dry with materialthe organic layers were dried (MgSO4)
6. concentrationconcentrated
7. customto give a thick amber oil
8. customchromatographed over silica gel in 75:25 to 70:30 hexane/ethyl acetate yielding 330 mg of yellow crystals