- METHOD FOR SYNTHESIZING BETA-DICARBONYL COMPOUNDS
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A method for synthesizing beta-dicarbonyl compounds, particularly beta-diketones, from at least two carbonyl compounds, such as esters and ketones, in the presence of a strong base or a mixture of strong bases by Claisen condensation with a titer of greater than 95%. The method includes providing a synthesis reactor on which a separation column, provided with a condenser and with at least one microwave generator, is mounted; feeding a first carbonyl compound and the strong base into the synthesis reactor; heating the reactor and starting up the condenser; starting up the microwave generator(s); when the mixture is brought to a boil at total flux, feeding the second carbonyl compound into the reactor; and after a waiting time, stopping the reactor and acidifying and washing the reaction mixture.)
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Paragraph 0125; 0126; 0127; 0128; 0129
(2014/04/03)
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- Process for base-promoted condensation reactions and base reagent therefor
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A method for the preparation of 1,3-diketones is disclosed wherein the method comprises the steps of:(A) mixing an alkali metal base with a hindered alcohol in an aromatic hydrocarbon solvent;(B) boiling the mixture and azeotropically distilling water formed by the reaction between the base and the alcohol, whereby a solution of a hindered alkali metal alkoxide is formed in situ in the solvent;(C) mixing an ester with the solution of the hindered alkali metal alkoxide in the aromatic hydrocarbon solvent; and then(D) adding a ketone to the mixture.
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- Process for the preparation of aromatic beta-diketones
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A process is disclosed for the preparation of aromatic beta-diketones by the reaction of an acetophenone and a molar excess of an aliphatic ester or an ester of benzoic acid in the presence of sodium alkoxide condensation agent in an aromatic hydrocarbon solvent at a temperature in the range 120-170oC. The solvent and excess ester reactant may be recycled after separation of the aromatic beta-diketone product.
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- Process for the preparation of aromatic beta-diketones
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A process for the preparation of aromatic beta-diketones by the reaction of an acetophenone and a molar excess of an alphatic ester or an ester of benzoic acid in the presence of sodium alkoxide condensation agent in an aromatic hydrocarbon solvent. Also disclosed is a method of recycling the solvent and excess ester reactant after separation of the aromatic beta-diketone product.
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