反应详情

A mixture of the product of Step A (0.94 g; 3.35 mmol), KOH (0.56 g; 10 mmol), H2O (2 ml) and dioxane was stirred at reflux overnight. After evaporation of solvents under reduced pressure, the residue was dissolved on H2O (5 ml) and insoluble material was removed by filtration. The filtrate was acidified to pH˜3 with diluted HCl and the product was taken up by extraction with CH2Cl2 (3×15 ml). The combined organic phase was dried over anhydrous MgSO4, filtered and filtrate evaporated to dryness to give the title compound (0.75 g; 94%) as creamy solid. 1H-NMR (CDCl3) 1.02-1.08 (m, 6H); 1.79-1.93 (m, 4H); 3.98-4.05 (m, 4H); 6.87 (d, 1H, J=8.5 Hz); 7.57 (d, 1H, J=2 Hz)); 7.7 (dd, 1H, J=2, 8.5 Hz).

1. temperatureat reflux overnight
2. customAfter evaporation of solvents under reduced pressure
3. dissolutionthe residue was dissolved on H2O (5 ml) and insoluble material
4. customwas removed by filtration
5. extractionthe product was taken up by extraction with CH2Cl2 (3×15 ml)
6. dry with materialThe combined organic phase was dried over anhydrous MgSO4
7. filtrationfiltered
8. customfiltrate evaporated to dryness