Malonic acid, diethyl ester

The starting material is prepared by reacting 2-amino-6-methylpyridine with ethoxymethyl-ene-malonic acid diethyl ester and then reacting that product with sodium hydroxide. 

Ethoxymethylene malonic acid diethyl ester Diethyl sulfata... 

The starting material may be produced by reacting 6-amino-2-methylthiopyrimidine with ethoxymethylene malonic acid diethyl ester. The intermediate thus produced is converted by boiling in diphenyl ether to 6-ethoxycarbonyl-2-methylthio-5-oxo-5,B-dihydropyrido-[2,3-d]pyrimidine. That is hydrolyzed by sodium hydroxide to cleave the ethoxy group and then ethylated with diethyl sulfate to give the starting material. 

Nit ropheny I) pyridine Ethoxymethylene malonic acid diethyl ester Ethyl iodide Sodium hydroxide... 

C)H7CI03 5538-51-2) see Benorilate Phenprocoumon (2-acetoxybenzoyl)(l-phenylpropyl)malonic acid diethyl ester... 

C3H5S 870-23-5) see Altizide allyl(l-methyl-2-pentynyl)malonic acid diethyl ester (C16H24O4 101448-52-6) see Methohexital 4-allyloxy-3-chlorobenzaldehyde (CigH Cl02, 58236-91-2) see Alclofenac 4-allyloxy-3-chlorobenzyl chloride (C Hi()Cl20 20788-43-6) see Alclofenac 4-allyloxy-3-chlorobenzyl cyanide (C, H C1N0 20788-44-7) see Alclofenac... 

Diethyl malonate Malonic acid, diethyl ester (8) Propanedioic acid, diethyl ester (9) (105-53-3)... 

Benzisot hiazole-3-malonic acid diethyl ester... 

Malonic acid diethyl ester Ethyl bromide... 

By interaction of malonic acid diethyl ester with sodium ethylate (molar ratio 1 1) and then with ethyl bromide (molar ratio 1 1) was prepared ethylmalonic... 

Phenyl ethyl malonic acid diethyl ester Methylurea... 

P-Phenylmercaptoethyl)-malonic acid diethyl ester Manufacturing Process... 

Fig. 12.9. Nitrosation of malonic acid diethyl ester. The mechanism of the acid-catalyzed enolization malonic ester malonic ester enol (E) and the mechanism of the actual nitrozation (E -> A) is shown here.

An aqueous solution of sodium nitrite that is treated with HC1 contains nitrosyl cations 0=N . These can react with the enol E of the malonic acid diethyl ester (cf. Figure 12.9, bottom). First, a nitroso compound (F) is formed, which then undergoes acid-catalyzed isomerization to give the oxime A. Usually, the oxime is reduced by zinc, which is dissolved in acetic acid, to yield an amine that normally undergoes in situ acetylation in acetic acid. In this way the (acetamido)malonic acid diethyl ester B is obtained as the reduction/acetylation product, which can be employed, for example, in the synthesis of amino acids (Figure 13.39). 

Fig. 12.11. Mechanism of the tert-butylation of malonic acid diethyl ester. From the point of view of tert-butyl chloride it is an SN1 reaction with the malonic ester enol (B) acting as the nucleophile.

It can be assumed that the small amount of piperidine in the reaction mixture is completely protonated by malonic acid because piperidine is more basic than pyridine. Hence, only the less basic pyridine is available for the formation of the malonic acid enolate D from free malonic acid and for the formation of the malonic acid dianion from the malonic acid mono-carboxylate C. The pKa value of malonic acid with regard to its C,H acidity should be close to the pKa value of malonic acid diethyl ester (p= 13.3). The pKa value of malonic acid monocarboxylate C with regard to its C,H acidity should be larger by at least a factor 10. Hence, the concentration of the malonic acid enolate D in the reaction mixture must be by many orders of magnitude higher than that of any malonic acid dianion. Due to the advantages associated with this enormous concentration D could be the actual nucleophile in Knoevenagel condensations. 

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