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Acetyl-malonic ester

In 1939, Gould and Jacobs reported the condensation of aniline with acetyl malonic ester (AME) and ethoxymethylenemalonate (EMME), respectively, followed by cyclization of anilinomethylenemalonic ester 13 and 14 in mineral oil to afford the esters 15 and 16. Saponification of the esters gave the known acids 17 and 18, respectively. [Pg.424]

In the electrolysis of cyan-acetic ester the formation of dicyan-succinic ester could not be observed likewise a union of the anions of benzyl-malonic ester, acetyl-malonic ester, and acetyl-dicarboxylic ester did not take place. Electrolysis of acid amides in the... [Pg.63]

Tosylation of 1146 gave 1147, which was converted to the iodo derivative, whose reaction with the sodium salt of guanine, followed by acetylation to aid its purification and then deprotection, gave 1148 (86JMC1384). The hydroxymethyl groups on C-5 of barbituric acid were introduced starting with malonic ester and then reaction with urea (93MI12). [Pg.186]

A condensation occurs between 5-hydroxymethylfurfural and malonic ester20 and in a similar way, two molecules of malonic ester react with furan 2,5-dialdehyde.88 A condensation product, XXXV, has also been obtained with hydantoin.89 5-Hydroxymethylfurfural and its acetyl derivative undergo the Perkin reaction with sodium acetate and acetic anhydride giving 5-acetoxymethylfuran 2-acrylic acid (XXXVI).70 Similar products of the same reaction are obtained from 5-methyl-furfural71 and 5,5 -diformyl-l,l -furylmethyl ether (XXVII).61,72... [Pg.102]

Three methods for the conversion of 3-chlorocarbonyl-1,2,5-thiadiazole (81) to ketones were investigated by Gill. The Lund procedure for the malonic ester synthesis of ketones proved quite successful for the preparation of 3-acetyl-1,2,5-thiadiazole (83). Condensation of 81 with diethyl ethoxymagnesiomalonate provides the ketodiester (82) which undergoes acid hydrolysis and decarboxylation to 83 in 90 % yield. The same reaction sequence employing the sodio derivative of malonic ester was much less efficient. [Pg.135]

C-Alkylation of the sodio derivative is accomplished by a technique similar to the alkylation of malonic ester. Primary halogen compounds, quaternary ammonium salts,and an alkene oxide have been used as alkylating agents. Alkylation by secondary halides has been less successful. Hydrolysis of the substituted esters to acetylated amino acids is described for leucine (64%) and phenylalanine (83%). Hydrolysis with deacylation has been used to prepare histidine (45%) and phenylalanine (67%). Glutamic acid (75%) is obtained from substituted acylaminomalonates prepared by the Michael condensation of methyl acrylate and the acylated amino esters. ... [Pg.223]

Z)-2-butenylene dicarbonate with dimethyl malonate gives a low yield (20—40%) of 2-vinylcyclopropane-l,l-dicarboxylate with up to 70% ee (Scheme 2-38) [54], Reaction with methyl acetoacetate or acetylacetone takes place in a different manner to give a dihydrofuran derivative (59% ee), which results from nucleophilic attack of enolate oxygen at the cyclization step, (c) Asymmetric elimination of an acetyl-acetate ester gives (R)-4-rerr-butyl-l-vinylcyclohexene of up to 44% ee (Scheme 2-39) [55]. (d) Palladium-catalyzed allylic silylation is also applied to asymmetric synthesis... [Pg.127]

Tetrahedral intermediates have been shown to be kinetically important in the S->N transfer reaction of S-acetylmercaptoamine (Martin and Hedrick, 1962) the O N transfer reaction of 0-acetylethanolamine (Hansen, 1963), intramolecular-aminolysis of ethyl y-aminobutyrate, ethyl 8-aminovalerate, and related reactions (Martin et al., 1964), hydrolysis of thiazolines (Martin et al., 1959 Martin and Parcell, 1961a Schmir, 1965), hydrolysis of oxazolines (Martin et al., 1964 Greenhalgh et al., 1963 Martin and Parcell, 1961b), hydrolysis of 2-imidazolines (Harnsberger and Riebsomer, 1964), and in the hydrolysis of acetyl-malonate diethyl ester (Lienhard and Jencks, 1965). [Pg.261]

The first synthesis of rfZ-deoxynupharidine was reported by Kotake et al. (30). The starting material w as 2,5-lutidine which was made to react with formaldehyde to give the diol XXVII on dehydration, acetylation, and condensation with malonic ester XXVII afforded the diester XXVIII. On hydrogenation and acid hydrolysis XXVIII was decarboxylated to the valeric acid derivative XXIX. After esterification the acid was acylated with 3-furoyl chloride and distilled with soda lime to yield dehydrodeoxynupharidine (XXX), and this on hydrogenation gave dl-deoxynupharidine (II). [Pg.452]

The reactions of perfluoroisobutene with sodium salts of malonic esters are difficult to control, owing to rearrangement and base catalysed cyclization, but when the complex BFs NEts is used as HF acceptor, condensation is readily controlled (see Scheme 15 and p. 99) and yields of up to 50% of allene (39) obtained. Antimony pentaliuoride catalyses the electrophilic addition of acid fluorides to 1,1-difluoro- and trifluoro-ethylene. Propiophenones, PhCO CHX-CFs (X = H or F), are obtained from benzoyl fluoride, but with acetyl fluoride, further condensation occurs, and trifluoroethylene yields the jS-diketone, CF3-CHF-CO-CH2Ac. ... [Pg.68]

High-dilution conditions for the intramolecular application of the malonic ester synthesis to the preparation of macrocyclic diesters have been reported yields between 9 and 50% are obtained. Dialklacyl phosphonates provide a new method for the acetylation of enolates including the sodium enolate of diethyl malonate. An alternative method for the generation of diester enolates involves the reductive a-deacetoxylation of an a-acetoxy diester (Scheme 30). The... [Pg.111]

While the preceding malonic ester synthesis enables elongation of the labeled acetyl carbon chain by two carbon atoms, extension by one carbon is achieved when [ C]acetyl chloride is treated with diazomethane followed by quenching of the resulting diazoketone with gaseous HCl. The product in this example, l-chloro[2- C]propan-2-one (3), may... [Pg.291]

With active methylene compounds, the carbanion substitutes for the hydroxyl group of aHyl alcohol (17,20). Reaction of aHyl alcohol with acetylacetone at 85°C for 3 h yields 70% monoaHyl compound and 26% diaHyl compound. Malonic acid ester in which the hydrogen atom of its active methylene is substituted by A/-acetyl, undergoes the same substitution reaction with aHyl alcohol and subsequendy yields a-amino acid by decarboxylation (21). [Pg.73]

The intense reddish-brown color of the acetylacetone titanium complexes impart a yellow discoloration to white inks. This discoloration is accentuated when the inks are used to print substrates that contain phenol-based antioxidants. The phenoHc compounds react with the organic titanate to form a highly colored titanium phenolate. Replacement of 0.25 to 0.75 moles of acetylacetone with a malonic acid dialkyl ester, such as diethyl malonate, gives a titanium complex that maintains the performance advantages of the acetyl acetone titanium complexes, but which is only slightly yellow in color (505). These complexes still form highly colored titanium phenolates. [Pg.163]


See other pages where Acetyl-malonic ester is mentioned: [Pg.569]    [Pg.16]    [Pg.214]    [Pg.569]    [Pg.16]    [Pg.214]    [Pg.113]    [Pg.162]    [Pg.113]    [Pg.362]    [Pg.371]    [Pg.271]    [Pg.162]    [Pg.1333]    [Pg.113]    [Pg.362]    [Pg.802]    [Pg.1335]    [Pg.1335]    [Pg.162]    [Pg.1333]    [Pg.319]    [Pg.169]    [Pg.2005]    [Pg.65]    [Pg.188]    [Pg.350]    [Pg.205]   
See also in sourсe #XX -- [ Pg.424 ]




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Acetyl esters

Ester acetylation

Malonate esters

Malonic ester, acetyl-, reaction with

Malonic ester—

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