| The thesis has two parts:oxidative cross-coupling of 1,3-dicarbonyl compounds with (NH4)2Ce(NO3)6 and its reaction with intermediate of Lactonamycin.Coupled reaction is one of the most important methods in the construction of carbon-carbon bonds.Coupling of derivatives of ethyl benzoylacetate was developed.With ethyl benzoylacetate as a standard model substrate,the influences of reaction temperature, equivalent,solvent and reaction time were studied,the coupled product of diethyl 2,3-dibenzoylsuccinate could be obtained with 83%yield when the reaction was carried out with 1.1 eq.CAN at -20℃for 4h.With the optimal condition obtained,different substituted arylβ-ketoesters were tested.The results showed that the electron-donating groups on the phenyl ring could increase the yield while the electron-withdrawing groups gave the opposite results due to too high reaction activity.In order to the checked scope of the substrates,the oxidative cross-coupling reaction of diketone by CAN was tested.The coupling of benzoyl acetone with optimum conditions was carried out and the yield was 88%.The influence of the substituent positions and electronic nature of the phenyl ring on the yield of the reaction was also tested.The possible mechanism of the oxidative cross-coupling of 1,3-dicarboyl compounds by CAN was proposed.The other content of the thesis was developed a method for synthesis of Lactonamycin.After several steps,we obtained intermediate,a semi acetal 52.Oxidation of 52 to quinone 53 was our aim.Different conditions were tested in order to obtain optimum quantity of 53.After investigating the effects of the dosage of CAN,reaction time, reaction temperature,we obtained the optimum reaction conditions for synthesis of 53 and cross-coupling products,the single-molecule oxidation product with yield 98%could be obtained at -15℃with 3 eq.CAN for 15 min,the product of bimolecular coupling are obtained while the reaction time has been extended to 24 h(41.3%yield).
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