Methyl malonate

The TT-allylpalladiLim complexes formed as intermediates in the reaction of 1,3-dienes are trapped by soft carbon nucleophiles such as malonate, cyanoacctate, and malononitrile[ 177-179). The reaction of (o-iodophenyl-methyl) malonate (261) with 1,4-cyclohexadiene is terminated by the capture of malonate via Pd migration to form 262. The intramolecular reaction of 263 generates Tr-allylpalladium, which is trapped by malononitrile to give 264. o-[odophenylmalonate (265) adds to 1,4-cyciohexadiene to form a Tr-allylpalladium intermediate via elimination of H—Pd—X and its readdition, which is trapped intramolecularly with malonate to form 266)176]. 

Sodium ionophore VI bis[(12-crown-4)methyl]dodecyl methyl malonate [80403-59-4] M 662.9. Purified by gel permeation or column chromatography. [Preparation and NMR data J Electroanal Chem 132 99 1982.]... 

Methyl Malonate.—This ester is an artificially prepared body, having a fruity odour, somewhat similar to the above-described esters of the fatty acids. It has the formula CH2(C02CHg)2, and boils at 181°. It may be prepared by treating potassium cyan-acetate with methyl alcohol and hydrochloric acid. On saponification with alcoholic potash it yields malonic acid, which melts at 132°, and serves well for the identification of the ester. 

This ester (70 g) and diethyl carbonate (250 mg) were stirred at 90°C to 100°C while a solution of sodium ethoxide [from sodium (7.8 g) and ethanol (1 54 ml)] was added over 1 hr. During addition, ethanol was allowed to distill and after addition distillation was continued until the column heat temperature reached 124°C. After cooling the solution to 90°C, dimethyl sulfate (33 ml) was followed by a further 85 ml of diethyl carbonate. This solution was stirred and refluxed for 1 hr and then, when Ice cool, was diluted with water and acetic acid (10 ml). The malonate was isolated in ether and fractionally distilled to yield a fraction boiling at 148°C to 153°C/0.075 mm, identified as the alpha-methyl malonate. This was hydrolyzed by refluxing for 1 hr at 2.5N sodium hydroxide (350 ml) and alcohol (175 ml), excess alcohol was distilled and the residual suspension of sodium salt was acidified with hydrochloric acid to give a precipitate of the alpha-methyl malonic acid. This was decarboxylated by heating at 180°C to 200°Cfor 30 minutes and recrystallized from petroleum ether (BP 80°C to 100°C) to give 2-(2-fluoro-4-biphenylyl)propionic acid, MP 110°C to 111°C. 

The residual oil was stirred and refluxed with sodium hydroxide (75 ml of 5N), water (45 ml) and 95% ethanol (120 ml). Within a few minutes a sodium salt separated and after 1 hour the solid was collected, washed with ethanol, dissolved in hot water and acidified with dilute hydrochloric acid to give the methyl malonic acid which was collected and dried in vacuo MP 177° to 180°C (dec.). 

Diethyl-sec-butyl methyl malonate Lithium aluminum hydride Ethyl urethane... 

Diethyl malonate, reaction with formaldehyde to form diethyl bis-(hydroxy methyl) malonate, 40, 27... 

CHjlMg 917-64-6) see Calcifediol Dexamethasone Fenpentadiol Indalpine Mesterolone Methyltestosterone Nabilone Paramethasone Tiaprofenic acid Troglitazone methyl malonamate (C4H7NO, 51513-29-2) see Cefotetan methyl malonate lithium salt (C4H,Li04 63460-24-2) see Misoprostol methyl mercaptane... 

Cobalt is present in animals in vitamin B12 (cyanocobalamine) and thus is essential for humans (Thunus and Lejeune 1994). The determination of Co has little significance for the diagnosis of deficiency of cyanocobalamine. Instead, cyanocobalamine itself must be determined in serum. The determination of methyl malonic acid in urine seems more reliable (McCann et al. 1996). 

McCann MT, Thompson MM, Gueron IC et al. (1996) Methyl malonic acid quantification by stable isotope dilution gas chromatography-mass spectrometry from filter paper urine samples. Clin Chem 42 9io-9i4. 

By modification of method A, Jones has transformed 2,4-bis-OBoc-benzy-aldehyde 5 into the 3-carbomethoxy dihydrocoumarin 43 in 68% yield (Fig. 4.23).lla The reaction proceeds by the addition of phenyl Grignard followed by addition of a preformed mixture of methyl malonate and sodium hydride and warming to room temperature. This particular example obviates the need for prior initiation by an organolithium reagent. 

Crowded imidazolides do not react with magnesium bis (methyl malonate) because of steric hindrance. 551... 

Decenoic acid (143), easily prepared from the same telomer 142, was cyclized via acid chloride using A1C13 to give 2-pentyl-2-cyclopentenone (144). Michael addition of methyl malonate followed by removal of one ester group produced methyl dihydrojasmonate (145) (129) ... 

An NMR investigation of water exchange at [Pt(H20)2(oxalate)2] is relevant to the mechanism of formation of one-dimensional mixed valence oxalatoplatinum polymers. In fact the rate constant for this presumably dissociative (AS = + 42 JK mol-1) reaction is considerably too low for water loss to be, as recently proposed, the first step in formation of these polymers. The mechanism of trans to cis isomerization for this oxalate complex, and for its (2 -methyl)malonate analogues, is intramolecular (Bailar or Ray-Dutt twist), since there is no concurrent incorporation of labeled solvent (177). 

The first successful attempt in asymmetric synthesis was made by Marckwald in 1904 who prepared an active (-) -valeric acid by heating the half brucine salt of ethyl methyl malonic acid at 170°C. 

Rearrangement of Alkylcobalt Carbonyls Takegami et al. [25) reported that when ethyl ot-bromopropionate is treated with KCo(CO)4 in toluene at 0° in the presence of 1 atm of CO and the product cleaved with iodine, both the expected ester, ethyl methyl-malonate, and the rearranged ester, diethyl succinate, are formed, the latter in smaller quantity. At 25°, however, the succinate predominates. 

A potential industrial route to potassium dinitromethane (18) involves treatment of methyl malonate (107) with red fuming nitric acid to give methyl Q ,Q -dinitroacetate (108), followed by hydrolysis-decarboxylation with aqueous potassium hydroxide. Dinitromethane is a precursor to 2,2-dinitroethanol and 2,2-dinitro-1,3-propanediol, both of which are useful in addition and esterification reactions for the production of energetic oligomers and plasticizers. 

Blechert reported a skillful method of cross-enyne metathesis. Solid-supported alkyne 139 is reacted with alkene in the presence of Ic to give 140. For cleavage of 1,3-diene from solid-supported product 140 having an allyl acetate moiety, palladium-catalyzed allylic substitution is used. Thus, 140 is treated with Pd(PPh3)4 in the presence of methyl malonate to afford three-component coupling product 141 in good yield ... 

During an investigation of the synthesis of oxazole-4-carboxylates, Shapiro reported that chlorination of amino[(phenylthio)methyl]malonate derivatives 91 with A -chlorosuccinimide (NCS), followed by treatment with Hunig s base, afforded the oxazolines 93. The oxazolines 93 were then converted to the respective oxazole-4-carboxylates 94-97 through decarbomethoxylation and elimination of thiophenoxide in the presence of methyl iodide. Methyl iodide traps the ejected thiophenoxide that would otherwise demethylate the oxazole-4-carboxylate (Scheme 8.31). " ... 

In the next stage the introduction of a fluorine atom onto the chiral center was examined with some 2-fluoro-2-alkyl malonic acid diesters with lipases. When the hydrolysis of 2-fluoro-2-methyl malonic aicd diester was examined with pig... 

Diabetes - insulin dependent Methyl malonic, propionic or isovaleric acidaemias Pyruvate carboxylase and multiple carboxylase deficiency Gluconeogenesis enzyme deficiency glucose-6-phosphatase, fructose-1,6-diphosphatase or abnormality of glycogen synthesis (glycogen synthase) Ketolysis defects Succinyl coenzyme A 3-keto acid transferase ACAC coenzyme A thiolase... 

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