[CH3:1][C:2](=O)[CH2:3][C:4](=[O:6])[CH3:5].Br[CH2:9][CH2:10][CH2:11][CH2:12][CH2:13][CH2:14][CH2:15][CH2:16][CH2:17][CH2:18][CH2:19][CH2:20][CH2:21][CH2:22][CH2:23][CH2:24]CC.C1OCCOCCOCCOCCOCCOC1.C(=O)([O-])[O-].[K+].[K+]>O.C(O)C>[CH3:5][C:4](=[O:6])[CH2:3][CH2:2][CH2:1][CH2:24][CH2:23][CH2:22][CH2:21][CH2:20][CH2:19][CH2:18][CH2:17][CH2:16][CH2:15][CH2:14][CH2:13][CH2:12][CH2:11][CH2:10][CH3:9]To a 2 L two-necked round bottom flask equipped with water condenser, calcium chloride guard tube and mechanical stirrer, 70 g of 2,4-pentanedione, 650 g of 1-bromooctadecane, 8 g of 18-crown-6, anhydrous potassium carbonate 140 g and 600 ml of absolute ethanol were added with stirring. The mixture was refluxed at 90° C. with continuous stirring for 30 hrs; after refluxing at the said temperature, the mixture cooled to ambient temperature (25° C.), 600 ml of water was added to it and the 2-heneicosanone was extracted with dichloromethane from the mixture. On distillation of dichloromethane, 2-heneicosanone was obtained.
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