反应详情

A solution of guanidine nitrate (1.5 g, 12 mmol) in EtOH (9 mL) was treated with 3 mL of 1 M EtONa in EtOH, refluxed for 15 minutes, cooled, treated with a solution of Example 41A in EtOH (5 mL), heated at reflux overnight, cooled, treated with water (25 mL) and extracted with CH2Cl2 (3×25 mL). The combined CH2Cl2 layers were dried (MgSO4), filtered, concentrated under reduced pressure and chromatographed on silica gel eluting with a gradient of CH2Cl2:EtOAc (1:0 and 20:1) to provide the title compound. 1H NMR (DMSO-d6) δ 2.46 (s, 3H), 5.18 (s, 2H), 6.31 (s, 2H), 7.29 (m, 1H), 7.42-7.51 (m, 2H), 7.96 (m, 1H). MS (M+H)+ m/z 246.

1. temperaturerefluxed for 15 minutes
2. temperaturecooled
3. temperatureheated
4. temperatureat reflux overnight
5. temperaturecooled
6. extractionextracted with CH2Cl2 (3×25 mL)
7. dry with materialThe combined CH2Cl2 layers were dried (MgSO4)
8. filtrationfiltered
9. concentrationconcentrated under reduced pressure
10. customchromatographed on silica gel eluting with a gradient of CH2Cl2:EtOAc (1:0 and 20:1)