Sodiomalonic ester

Tricarbethoxymethane has been prepared by the action of ethyl chloroformate upon sodiomalonic ester in benzene suspension and by distillation of ethyl ethoxalylmalonate. The present method has been described briefly by one of the authors." It is simpler and gives better yields than the method described in Org. Syn. 13, 100, for the preparation of the corresponding methyl ester. 

From dibromomalonic ester and sodiomalonic ester. Adickes, J. prakt. Chem. (2) 145, 236 (r936). 

The magnesium enolates are prepared by treatment of malonic acid half ester either with magnesium ethylate[24],[32] or with isopropylmagnesium bromide[24] or chloride.t26] Ref. [23] describes the synthesis of a 13C-labelled ethyl acetoacetate. Concerning the synthesis of porphyrin / -ketoesters,[3 1 it was noticed that the method via imidazolides is more efficient than the other approach via acid chlorides and sodiomalonic esters. 

The above method is adapted from the procedure of Day and Thorpe.1 /3-Methylglutaric acid has been prepared by hydrolysis of jS-methylglutaronitrile 2 by condensation of crotonic ester with ethyl sodiocyanoacetate, and with sodiomalonic ester 3 4 and by condensation of acetaldehyde with malonic ester. ... 

This method is based on the general procedure previously described by Floyd and Miller.2 Cetylmalonic ester has also been prepared by condensation of ethyl stearate with ethyl carbonate 8 and by alkylation of sodiomalonic ester with cetyl iodide4 or cetyl bromide.8... 

Ethyl benzalmalonate has been prepared by the esterification of benzalmalonic acid in the presence of concentrated sulfuric acid 4 by the action of benzal chloride on sodiomalonic ester 6 by the condensation of benzaldehyde and malonic ester in the pres-... 

The sodiomalonic ester synthesis was used in the preparation of /3-(quinuclid-2-yl)propionic acid (95) starting from 2-bromomethyl-quinuclidine,128 and y-(quinuclid-3-yl)butyric acid from 3-(j9-chloro-ethyl)quinuclidine.125... 

Various methods have been used to lengthen a carbon side chain, in the syntheses of quinuclidyl-3-acetic acid (113) (Scheme 1). The lowest yield is in the sodiomalonic ester synthesis (13.4% ).125 Much better results are afforded by the Reformatsky reaction (40%)125 and Knoevenagel condensation (65-70%).129 The best yield (nearly quantitative) may be obtained by application of the Wittig-Horner reaction.155... 

Cundall, R. B. Sodiomalonic ester as an anionic catalyst. Proc. Chem. Soc. 1958, 170-171. 

Two other recently published methods allow the synthesis of 4,6-disubstituted dithiopyrones (8), although the yields are low. The action of nucleophilic agents (e.g., sodiomalonic ester) on 3,5-di-... 

The terminators for vinyl ether polymerizations include the sodium salt of ethyl malonate [sodiomalonic ester Na CH(C02C2H5)2] [131],... 

Sodiomalonic esters behave like organometalic reagents toward alkene oxides. Acid hydrolysis of the adduct accompanied by decarboxylation and lactonization furnishes a-substituted lactones in high yields. "y-Substituted y-butyrolactones result from sodiomalonic ester and substituted ethylene oxides. ... 

CH(COOC2H5)2-Na+ + HOC2H5 Sodiomalonic ester Weaker acid... 

Problem 26.2 Adipic acid is obtained from a malonic ester synthesis in which the first step is addition of one mole of ethylene bromide to a large excess of sodio-malonic ester in alcohol. Cychpropanecarboxyiic acid is the final product of a malonic ester synthesis in which the first step is addition of one mole of sodiomalonic ester to two moles of ethylene bromide followed by addition of one mole of sodium ethoxide. 

Treatment of the 2-oxazoline with the strong base, w-butyllithium, yields the lithio derivative II. This, like sodiomalonic ester, can be alkylated and, if desired, re-alkylated—up to a total of two substituents on the a-carbon. Ethanolysis of the new 2-oxazoline yields the substituted ester. 

N + sodiomalonic ester then OH, heat then H then heat -... 

Another type of reaction which has been realized with the allyl system is the so-called Sn2 displacement. Here the attacking reagent strikes an atom different from the one to which the halogen atom is attached. An allylic shift occurs, and the halogen atom is displaced. Thus, when 3-chloro-l-pentene (XVI) is allowed to react with sodiomalonic ester, 2-pentenyl malonic ester is obtained (XVII).19 Second-order kinetics... 

Such a reaction would involve addition of the halogen atom to the y-carbon atom of the allyl alcohol, a simultaneous shift of the double bond and elimination of a molecule of sulfur dioxide. The sequence is similar to what must occur when sodiomalonic ester reacts with ethylvinyl-carbinyl chloride (X) to give XI. (See p. 92.)... 

Interestingly, enamines attack the terminal olefinic carbon of l,l-bis(ethoxycarbonyl)-2-vinylcyclopropane (42), with ring opening of the cyclopropane ring, in contrast to sodiomalonic ester which attacks the more substituted cyclopropane carbon. With diethyl cyclopropylmethylideneraalonate (43) reaction occurs at the jff-carbon and the cyclopropyl ring remains intact (Scheme 27). Titanium tetrachloride catalyses the highly diastereoselective addition of enamines to 2,2-dimethoxyethyl crotonate. ... 

Acylation of malonic esters. Monoacylation of sodiomalonic esters is usually accompanied by diacylation. This disadvantage can be eliminated by reaction of the sodiomalonate with trimethylchlorosilane to give a ketene acetal (1). This reacts readily with an acid chloride or anhydride to give an acylmalonic ester (2).11 Yields are in the range 50-80%. 

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