Ethyl 3-oxobutanoate acetoacetate

In Summary jS-Dicarbonyl compounds such as ethyl 3-oxobutanoate (acetoacetate) and diethyl propanedioate (malonate) are versatile synthetic building blocks for elaborating more complex molecules. Their unusual acidity makes it easy to form the corresponding anions, which can be used in nucleophilic displacement reactions with a wide variety of substrates. Their hydrolysis produces 3-ketoacids that are unstable and undeigo decarboxylation on heating. 

FCC) ETHYL ACETYLACETONATE ETHYL BENZYL ACETOACETATE ETHYL-3-OXO-BUTANOATE ETHYL-3-OXOBUTYRATE FEMA No. 2415 3-OXOBUTANOIC ACID ETHYL ESTER... 

F.52) Butanoic acid, 3-oxo-, ethyl ester, ethyl acetoacetate, ethyl 3-oxobutanoate, ethyl acetylacetate, acetoacetic acid ethyl ester, diacetic ether (1-41-97-9] FEMA 2415... 

Synonyms Acetoacetic acid ethyl ester Acetoacetic ester Diacetic ether Diacetyl ether EAA EEA Ethyl acetyl acetate Ethyl acelylacetonate Ethyl benzyl acetoacetate Ethyl 3-oxobutanoate Ethyl 3-oxobulyrate 3-Oxobutanoic acid ethyl ester Classification Aliphatic organic compd. 

EEA Ethyl acetyl acetate Ethyl acetylacetonate Ethyl benzyl acetoacetate Ethyl 3-oxobutanoate... 

The systematic lUPAC name of ethyl acetoacetate is ethyl 3 oxobutanoate The presence of a ketone carbonyl group is indicated by the designation oxo along with the appro priate locant Thus there are four carbon atoms m the acyl group of ethyl 3 oxobutanoate C 3 being the carbonyl carbon of the ketone function... 

Carbon is alkylated ia the form of enolates or as carbanions. The enolates are ambident ia activity and can react at an oxygen or a carbon. For example, refluxing equimolar amounts of dimethyl sulfate and ethyl acetoacetate with potassium carbonate gives a 36% yield of the 0-methylation product, ie, ethyl 3-methoxy-2-butenoate, and 30% of the C-methylation product, ie, ethyl 2-methyl-3-oxobutanoate (26). Generally, only one alkyl group of the sulfate reacts with beta-diketones, beta-ketoesters, or malonates (27). Factors affecting the 0 C alkylation ratio have been extensively studied (28). Reaction ia the presence of soHd Al O results mosdy ia C-alkylation of ethyl acetoacetate (29). 

Ethyl 3-oxobutanoate, commonly called ethyl acetoacetate or ace tome tic ester, is much like malonic ester in that its ct hydrogens are flanked by two carbonyl groups. It is therefore readily converted into its enolate ion, which can be alkylated by reaction with an alkyl halide. A second alkylation can also be carried out if desired, since acetoacetic ester has two acidic a hydrogens. 

The ethyl ester can also be prepared from ethyl acetoacetate (ethyl 3-oxobutanoate) by the method of Rodionov8 as well as via Steinkopf s method.3 Ethyl nitroacetate can be prepared in >70% yields from the dipotassium salt, ethanol, and sulfuric acid, with the addition of anhydrous magnesium sulfate in order to avoid the Nef reaction.9 The propyl and 2-propyl esters can also be obtained by this method. 

Aliphatics Fluorination Investigated in Micro Reactors Cas/liquid reaction 3 [CL 3] Fluorination of ethyl 3-oxobutanoate (ethyl acetoacetate) [15, 16]... 

Based on hydrogenations of model substrates, several new ligands promise to have a similar potential as those described above. For example, Ru-Solphos (Solvias) catalysts have been shown to hydrogenate various yS-keto esters and / -diketones with ee-values up to >99% and TONs of up to 100000 (for ethyl-3-oxobutanoate) [75], while Ru-Synphos (Synkem) [107] catalysts achieved 99.4% ee at an SCR of 7000 for the hydrogenation of ethyl acetoacetate (for ligand structures, see Fig. 37.28). 

The following example shows the self-condensation of ethyl acetate to give ethyl ace-toacetate (ethyl 3-oxobutanoate). Ethoxide is used as the base to avoid transesterification or hydrolysis of the ethyl ester (see Problem 22-34). The initial product is the enolate of ethyl acetoacetate, which is reprotonated in the final step. 

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