反应详情

To a solution of 2-chlorophenylacetone (7.14 g, 42 mmol) in CH2Cl2 (184 mL), PCC (27 g, 127 mmol, 3 eq) and pyridine (10 mL, 127 mmol, 3 eq) in three portions were added over five hours at reflux under vigorous stirring. After the addition was complete, the mixture was further refluxed under vigorous stirring for 21.5 h. The mixture was filtered through a pad of silica gel, washed the pad with CH2Cl2, and concentrated under reduced pressure to provide a dark red syrup. The residue was purified by column chromatography on a 120 g of Redi-Sep™ column using 0-15% gradient of EtOAc in hexane over 40 min as eluent to provide 1-(2-chlorophenyl)propane-1,2-dione as yellow liquid. 1H NMR (choroform-d) δ ppm 7.66 (1H, dd, J=7.6, 1.8 Hz), 7.48-7.54 (1H, m), 7.37-7.46 (2H, m), 2.58 (3H, s). Mass Spectrum (ESI) m/e=182.9 (M+1).

1. temperatureat reflux under vigorous stirring
2. additionAfter the addition
3. temperaturethe mixture was further refluxed
4. filtrationThe mixture was filtered through a pad of silica gel
5. washwashed the pad with CH2Cl2
6. concentrationconcentrated under reduced pressure
7. customto provide a dark red syrup
8. customThe residue was purified by column chromatography on a 120 g of Redi-Sep™ column
9. customover 40 min