Malonate esters, oxidation

An analogous sequence on acid, 29 (obtained by decarboxylative hydrolysis of the malonic ester), leads to carbromal (30). Dehy-drohalogenation of 30 by means of silver oxide affords the corresponding olefin, ectylurea (31), itself a sedative-hypnotic. 

Manganese in its various oxidation states, such as, Mn+7, Mn+4 and Mn+3, had been exploited in several studies. An electron transfer mechanism for the inter-molecular arylation of malonate esters in the presence of manganese (III) triacetate... 

Oxidative cross-coupling reactions of alkylated derivatives of activated CH compounds, such as malonic esters, acetylacetone, cyanoacetates, and certain ketones, with nitroalkanes promoted by silver nitrate or iodine lead to the formation of the nitroalkylated products.67 This is an alternative way of performing SRN1 reactions using a-halo-nitroalkanes. 

If the oxidation is slower than the decomposition, oxygen may affect the nature of reaction products. Thus, treating p-nitrocumyl chloride with sodium malonate ester in a flow of pure dry nitrogen yields a product of C-alkylation (route a in Scheme 5.12) the yield is 90%. Oxygen completely inhibits the C-alkylation, and the reaction gives p-nitrocumyl alcohol in the same yield (route b in Scheme 5.12) (Kornblum et al. 1968). 

Anodic oxidation of malonate esters in alkaline solution gives the dehydrodimerization product by carbon-carbon coupling. The reaction mechanism has been... 

Sulfinpyrazone Sulfinpyrazone, l,2-diphenyl-4,2-(phenylsulfinil)ethyl-3,5-pyrazolidine-dione (3.2.8), is an analog of phenylbutazone that is synthesized in the analogous manner of condensing hydrazobenzol with 2-(2-phenyltioethyl)malonic ester into pyrazolidinedione (3.2.7), and the subsequent oxidation of thiol ether by hydrogen peroxide in acetic acid into the sulfoxide, sulfinpyrazone (3.2.8) [70,71]. 

In addition to the application of malonic esters, four-membered ring compounds can also be realized by using methyl methylsulfanylmethyl sulfoxide (14) as the active methylene component.25 27 As demonstrated in the following scheme, when the potassium salt of methyl methylsulfanylmethyl sulfoxide is allowed to react with 1,3-dibromopropane, cyclobutanone dimethyl dithioacetal 5-oxide (16) is isolated in 97% yield.8,10 Of particular interest is that the... 

An electrochemical method for amination has been reported by Shono and co-workers.275 Derivatives of malonic esters containing an N-tosyl group were cyclized in high yields by anodic oxidation ... 

Sodium malonic ester and dibromcinnarnic ester react and a compound results which analyses for phenylcyclopropane 2,2,3 triester and is not oxidized... 

Adipic acid has been prepared by the following methods the action of silver1 or copper 2 on /3-iodopropionic acid the reduction of mucic add with phosphorus and iodine 3 the electrolysis of the potassium or sodium salts of monoethyl succinate 4 the condensation of ethylene chloride or bromide with malonic ester or cyanoacetic ester and subsequent hydrolysis 5 the oxidation of certain fractions of Baku petroleum 6 the oxidation of cyclohexanol or cyclohexanone with nitric acid 7 or potassium permanganate.8... 

Super-dry ethanol. The yields in several organic preparations (e.g. malonic ester syntheses, reductions involving sodium and ethanol, etc.) are considerably improved by the use of ethanol of 99.8 per cent purity or higher. This very high grade ethanol may be prepared in several ways from commercial absolute alcohol or from the product of dehydration of rectified spirit with calcium oxide. 

Melphalan and the racemic analog have been prepared by two general routes (Scheme I). In Approach (A) the amino acid function is protected, and the nitrogen mustard moiety is prepared by conventional methods from aromatic nitro-derivatives. Thus, the ethyl ester of N-phthaloyl-phenylalanine was nitrated and reduced catalytically to amine I. Compound I was reacted with ethylene oxide to form the corresponding bis(2-hydroxyethyl)amino derivative II, which was then treated with phosphorus oxychloride or thionyl chloride. The blocking groups were removed by acidic hydrolysis. Melphalan was precipitated by addition of sodium acetate and was recrystallized from methanol. No racemization was detected [10,28—30]. The hydrochloride was obtained in pure form from the final hydrolysis mixture by partial neutralization to pH 0.5 [31]. Variants of this approach, used for the preparation of the racemic compound, followed the same route via the a-acylamino-a-p-aminobenzyl malonic ester III [10,28—30,32,33] or the hydantoin IV [12]. 

Cyclizations that form a single carbon-carbon bond can be accomplished by oxidative cydization of unsaturated /3-diketones, /3-keto esters, or /3-keto amides 11 that lead to cycloalkanones, unsaturated /3-diketones, /3-keto esters, or malonate esters 12 that lead to cycloalkanes, and unsaturated esters, or amides 13 that lead to lactams or lactones (Scheme 3) [5, 6]. 

Aminothiazole, with acetaldehyde, 42 to 2-mercaptothiazoie, 370 4-Aminothiazole-2,5-diphenyl, to 2,5 di-phenyl-A-2-thiazoline-4-one, 421 Ammothiazoie-A -oxide, 118 2-Aminothiazoles. 12 acidity of, 90 and acrylophenone, 42 acylations of, with acetic acid. 53 with acetic anhydride, 52 with acyl halides, 48 with chloracetyl chloride, 49 with-y-chlorobutyrylchloride, 50 with 0-chloropropionylchloride, 50 with esters, 53 with ethy acrylate, 54 with indoiyl derivatives, 48 with malonic esters, 55 with malonyl chloride, 49 with oxalyl chloride, 50 with sodium acetate, 52 with unsaturated acyl chloride, 49 additions to double bonds, 40 with aldehydes, 98 alkylations, with alcohols, 38 with benzyhydryl chloride, 34 with benzyl chloride, 80 with chloracetic acid, 33 with chloracetic esters, 33 with 2-chloropropionic acid, 32 with dialkylaminoalkyl halides, 33 with dimethylaminoethylchloride, 35 with ethylene oxide, 34, 38... 

Dimethyl-dihydroresorcinol has always been made from mesityl oxide and malonic ester. The procedure given above is that of Vorlander.1... 

Methanetricarboxylic Acid.—Mulliken1 employed the method, which has already been discussed (p. 104), in the electrolysis of the sodium salt of the triethyl ester of this acid and obtained othanehexacarboxylic ester, besides some malonic ester. Further oxidation caused the formation of sodium bicarbonate ... 

Methyl ethyl acetic acid may be prepared from methyl ethyl malonic ester by hydrolysis and subsequent heating of the methyl ethyl malonic acid.1 The yield by this method, in the preparation of large quantities, is about 61 per cent of the theoretical amount based on the malonic ester used. The acid was first prepared by Saur2 from methyl ethyl acetoacetic ester. It has also been made by oxidation of the corresponding aldehyde with chromic acid.3... 

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