Cyanoacetic esters, acidity

Alkylation of the sodio derivative affords the C-substituted cyanoacetic ester, which when heated with dilute acid gives the mono-substitut acetic acid. 

AEyl chloride reacts with sodamide in Hquid ammonia to produce benzene when sodamide is in excess, hexadiene dimer is the principal product, with some trimer and tetramer (C24, six double bonds). AEylation at carbon atoms alpha to polar groups is used in the preparation of a-aEyl-substituted ketones and nittiles. Preparation of P-diketone derivatives, methionic acid derivatives, and malonic ester, cyanoacetic ester, and P-keto-ester derivatives, etc, involving substitution on an alpha carbon between two polar carbonyl groups, is particularly facEe. 

As enolate precursors can be used CH-acidic carbonyl compounds such as malonic esters, cyanoacetic esters, acetoacetic esters and other /3-ketoesters, as well as aldehydes and ketones. Even CH-acidic hydrocarbons such as indene and fluorene can be converted into suitable carbon nucleophiles. 

AT1 cm ). and therefore, these dyes are excitable not only with red (635 or 670-nm) but also with blue (380, 405, and 470 nm) diode lasers or LEDs (Fig. 1). Carbonyl containing substituents such as 1,3-indanedione, cyanoacetic ester, barbituric, and thiobarbituric acid form intramolecular H-bond with the polymethine hydrogens of the squaraine bridge. As a result, the molar absorptivities and quantum yields of these dyes are substantially decreased. 

The Knoevenagel-type condensation of salicylaldehydes with malonic acid [14, 27], malonic ester [28], cyanoacetic ester [29], or Meldrum s acid [30], is... 

Dihydrocorynantheine was obtained via similar steps from normal cyanoacetic ester 319 (172). Stereoselective transformation of the alio cyanoacetic ester 315 to the normal stereoisomer 319 was achieved by utilizing a unique epimerization reaction of the corresponding quinolizidine-enamine system (174). Oxidation of alio cyanoacetic ester 315 with lead tetraacetate in acetic acid medium, followed by treatment with base, yielded the cis-disubstituted enamine 317, which slowly isomerized to the trans isomer 318. It has been proved that this reversible eipmerization process occurs at C-15. The ratio of trans/cis enamines (318/317) is about 9 1. The sodium borohydride reduction of 318 furnished the desired cyanoacetic ester derivative 319 with normal stereo arrangement. The details of the C-15 epimerization mechanism are discussed by B rczai-Beke etal. (174). 

Valproic acid, 2-propylvaleric acid (9.4.3), is synthesized by the alkylation of cyanoacetic ester with two moles of propylbromide, to give dipropylcyanoacetic ester (9.4.1). Hydrolysis and decarboxylation of the carbethyoxy group gives dipropylacetonitrile (9.4.2), which is hydrolyzed into valproic acid (9.4.3) [12-15]. 

The carbon nucleophiles in amine-catalyzed reaction conditions are usually rather acidic compounds containing two electron-attracting substituents. Malonic esters, cyanoacetic esters, and cyanoacetamide are examples of compounds which undergo condensation reactions under Knoevenagel conditions.115 Nitroalkanes are also effective nucleophilic reactants. The single nitro group sufficiently activates the a hydrogens to permit deprotonation under the weakly basic conditions. Usually, the product that is isolated is... 

Pimelic acid has been prepared as a by-product of the reaction between trimethylene bromide and sodium cyanoacetic ester 1 by the action of carbon dioxide upon pcntamethylene-... 

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... 

Ingold, C. K. Powell, W. J. Experiments on the synthesis of the polyacetic acids of methane. Part II. Some abnormal condensations of malonic and cyanoacetic esters with haloge-nated methanes./. Chem. Soc. 1921, 119, 1222-1229. 

Cuprous cyanide, 4, 69 Cuprous Hydroxide, 7, 30 Cuprous oxide, 6, 6 7, 33 Cyanoacetic acid, 7, 22 Cyanoacetic ester (ethyl), 7, 21 Cyanohydrin Synthesis, 6, 58 a-CYANO-/3-PlIENYLACRYLIC ACID, 7, 20, 21... 

Controlled, stepwise dialkylation may be performed as exemplified in equation 73, which shows a typical malonic ester synthesis including hydrolysis and decarboxylation to give an a,a-dialkylated acid. Acetoacetic ester synthesis and cyanoacetic ester syntheses give ketones (CH3COCHRR ) and nitriles (RR CHCN), respectively. 

Alanine has been prepared by the catalytic reduction of cyanoacetic esters 1 or salts 2 by heating acrylonitrile,3 /3-amino-propionitrile,4 iw-(/3-cyanoethyl)-amine,5 /3-hydroxypropionitrile, /3-alkoxypropionitriles,7 u.s-(/3-cyanocthyl) ether,8 or bis-(fi-cyano-ethyl) sulfide 8 with aqueous ammonia at 150-225° by the hydrolysis of /3-aminopropionitrile with concentrated hydrochloric acid and subsequent removal of the acid with anion exchange resins.9 The method as described above has been published.10 Additional references to methods of preparation are given in connection with a procedure for the making of /3-alanine from suc-cinimide through the action of potassium hypobromite.11... 

SYNS CYANACETATE ETHYLE (GERMAN) CYANOACETIC ACID ETHYL ESTER CYANOACETIC ESTER ESTERE CIANOACETICO ETHYL CYANOACETATE ETHYL CYANOETHANOATE ETHYLESTER KYSEUNY KYANOCTOVE MALONIC ACID ETHYL ESTER NITRILE USAF KF-25... 

A more recent modification of the Sorensen process employs acylamino-cyanoacetic esters, RCONHCH(CN)CO,C2Hs, in place of the malonates. An alkylated acetylaminocyanoacetate may be hydrolyzed to an amino acid in acidic or basic medium. ... 

Simple saturated nitriles are seldom prepared by the decarboxylation of cyano acids derived from the cyanoacetic ester synthesis (cf. method 265). However, difunctional compounds are frequently obtained by this route, as in the preparation of a-methyl-y-phenoxybutyronitrile from /3-phenoxy-ethyl bromide and ethyl methylcyanoacetate (52% over-all). ... 

Cyano acetals, preparation, 598 Cyanoacetic ester condensation, 608 Cyanoacetic ester synthesis, 429, 601 Cyano acids, esterification, 481 preparation, 593, 607, 608 preparations listed in table 74, 622 a-Cyano acids, decarboxylation, 429, 601... 

Hydrolysis and Decarboxylation of Cl-Cyano Acids (Cyanoacetic Ester... 

The cyanoacetic ester synthesis with ethylene bromide is preferred to the malonic ester synthesis for the preparation of cyclopropanecarboxylic acid. ... 

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