Sodium diethyl-2-methylmalonate

Van Leeuwen et al. used several generations of carbosilane dendrimers with 4, 8, 24, and 36 diphenylphosphine end-groups (Figure 4.15) for the allylic alkylation reaction of allyl trifluoracetate with sodium diethyl 2-methylmalonate.[31]... 

The same ligand system was used in the allylic alkylation of allyl trifluoroacetate with sodium diethyl-2-methylmalonate showing a more or less constant conversion over 8 h (20 exchanged reactor volumes). This is in contrast to peripheral functionalized dendrimers (Section 4.4.2), which deactivated at longer reaction times. 

The palladium catalyst supported on the dendrimer with 24 phosphine end groups (2) was used in a CFMR. In the continuous process a solution of allyl trifluoroacetate and sodium diethyl 2-methylmalonate in THF (including -decane as an internal standard) was pumped through the reactor. Figure 4 shows the conversion as a function of the amount of substrate solution (expressed in reactor volumes) pumped through the reactor. The reaction started immediately after the addition of the catalyst, and the maximum conversion was reached after two reactor volumes had passed, whereupon a drop in conversion was observed. It was inferred from the retention of the dendrimer (99.7% in dichloromethane) that the decrease was not caused by dendrimer depletion, and it was therefore ascribed to the... 

Another example of a dendritic effect observed for a core-funtionalized dendritic catalyst was described by Oosterom et al. (19) for allylic alkylation reactions (Section II). The palladium complexes of 5 catalyzed the alkylation of 3-phenylallyl acetate with sodium diethyl methylmalonate. It was observed that the reaction rate decreased and the fraction of branched product increased with increasing generation number. 

Alternative methods of preparing the starting acids can be used, but are generally less convenient. Benzo[6 ]thiophene derivatives were prepared from 2-methyl-3-(2 -thenoyl)propionic acid, which was obtained either by reacting 2-thienylmagnesium iodide with methylsuccinic anhydride, or by coupling 2-bromoacetylthiophene with the sodium salt of diethyl methylmalonate (45JA1645). 

Chloropyrazine and derivatives have been shown to react with alkali metal derivatives of a phenylacetonitrile or of a phenylacetamide for example, 2-chloropyrazine treated with diphenylacetonitrile in toluene with sodium amide gave 2-(T-cyano-r,r-diphenylmethyl)pyrazine (68, R = H) (1021, 1022). 2-Chloro-5-phenylpyrazine(s) with diethyl methylmalonate and sodium hydride gave 2-(r,l -di(ethoxycarbonyl)ethyl]-5-phenylpyrazine(s) (363-365, 824, 825), and a similar reaction occurred with 2-chloropyrazine (364, 365,1023). 

The same type of reaction was observed with 2-chlorocyclohexanone and the sodium salts of dimethyl malonate and diethyl methylmalonate, affording bicyclo[3.1.0]hexan-6-ols (5) and with 2-chlorocycloheptanone and the sodium salts of diethyl malonate and diethyl methylmalonate, affording bicyclo[4.1.0]heptan-7-ols (6). ... 

Dimethyl malonate (4.04 g, 30.6 mmol), potassium t-butoxide (3.43 g, 30.6 mmol) and anhydrous N,N-dimethylformamide (15 ml) were mixed and stirred for 10 minutes in a nitrogen atmosphere at 90°C. The mixture was then cooled to room temperature, and to the cooled mixture was added a solution of diethyl 2-(3-chloro-4-nitrophenyl)-2-methylmalonate (5.04 g, 15.3 mmol) prepared in the manner as described in Japanese Patent Publication No. 47-45, 746) in anhydrous N,N-dimethylformamide (15 ml). The resulting mixture was stirred at 90°C for 3 hours, and then poured into 1 N hydrochloric acid (30 ml). The mixture was subjected to extraction using two portions of diethyl ether. The ether extracts were combined, washed successively with water and an aqueous saturated sodium chloride solution, and dried over anhydrous sodium sulfate. The dried extract was placed under reduced pressure to give 7.97 g of yellow oil. The oil was adsorbed on silica gel (16 g) and subjected to... 

The diethyl 2-[3-bis(methoxycarbonyl)methyl-4-nitrophenyl]-2-methylmalonate obtained above,(4.13 g, 9.71 mmol) was dissolved in acetic acid (40 ml). To the solution were added water (16 ml) and concentrated sulfuric acid (4 ml), and the resulting mixture was heated for 15 hours under reflux. The acetic acid was distilled off under reduced pressure. The residue was concentrated under reduced pressure after addition of toluene. The precipitated crystals were collected by filtration and washed with water to give 2.06 g of the desired compound as a pale brown crystalline product. The filtrate and washing were combined and subjected to extraction using ethyl acetate. The ethyl acetate portion was washed successively with water and an aqueous saturated sodium chloride solution, and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure to leave 0.32 g of 2-(3-carboxymethyl-4-nitrophenyl)propionic acid as a yellow crystalline product. The total amount was 2.38 g (yield 96.8%). 

Dialkylation of malonic ester proceeds in most cases almost as readily as monoalkylation. Diethyl ethylmalonate is alkylated equally well by s-octyl and n-butyl halides. Di-n-propylmalonic ester is prepared in one step from malonic ester and n-propyl bromide. Methylmalonic ester is alkylated by /3-phenylethyl bromide, and even a-naphthyl-malonic ester may be further alkylated by n-alkyl iodides. Difficulty is encountered, however, in introducing two s alkyl groups into malonic ester. A 23% yield of diisopropylmalonic ester is obtained from iso-ptopylmalonic ester, sodium triphenylmethide, and isopropyl iodide. ... 

A ,Af-Dimethylcyclopropaniminium fluorosulfate reacts with added carbanions such as the sodium salts of methyl 2-methyl-3-oxobutanoate or diethyl 2-methylmalonate in dichloromethane or dichloromethane/dimethyl sulfoxide to give the corresponding aminocyclopropylated species 1 in poor yield. ... 

The reaction of FITS compounds with the sodium salt of 2-methylcyclohexan-l,3-dione led to the 0-perfluoroalkylated and the C-perfluoroalkylated products. The ratio 0-derivatives C-derivatives was strongly dependent upon the reaction temperature, the C-perfluoroalkylated product predominating at lower temperature. Similar results were obtained with ethyl 2-methylacetoacetate. In the case of the sodium salt of diethyl 2-methylmalonate and of 2-nitropropane, only the C-perfluoroalkylated products were isolated. ... 

Weems, on electrolyzing the sodium salt of methylmalonic ester in alcoholic solution, obtained dimethyl-etharie-tetracarboxylic ester ethyl-malonic ester yielded diethyl-etkane-tetracarboxylic ester and aceto-acetic ester was changed to diacetyl-succinic ester. 

Rather than pyridine or ammonia, bases such as sodium hydride or sodium ethoxide can be used to generate a malonate enolate anion. Such enolates are easier to control, from a synthetic viewpoint, and allow a wider range of reactions. For this reason, they are collected into this section. An example is the reaction of the sodium enolate of diethyl 2-methylmalonate with the bromine moiety in phthalimide derivative 4.42. This displacement reaction was followed by removal of the phthalimidoyl group, hydrolysis of the esters and decarboxylation to give 2-methyl-6-aminohexanoic acid (4.4J),23 Phthalimide 4.42 was prepared by reaction of 1,4-dibromobutane with potassium phthalimide.23 The length of the carbon chain in the... 

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