4-Oxocarboxylic acid esters, 5-substituted

Oxime O-ally 1 ethers, 58, 10 4-Oxocarboxylic acid esters, 58, 81 4-Oxocarboxylic acid esters, 5-substituted, 58,82... 

The present method4 is simple, versatile, and efficient in contrast to eailier methods, which were multistep or preparatively unsatisfactory Various 5-substituted 4-oxocarboxylic acid esters can be prepared by this procedure.4... 

Amides and mono substituted amides of anthranilic acid react with y- or -oxocarboxylic acids to give the pyrrolo- or pyrido[l,2-a]quinazolines 76 ( = 0,Reactions were carried out under reflux in the presence of or without - p-toluenesulfonic acid. Instead of the carboxylic acids, the esters can be applied. 

The carbenoid reaction between alkyl diazoacetates and enol ethers, enol acetates and silyl enol ethers furnishes P-oxycyclopropane carboxylates (see Tables 2, 4, 5, 6, 7 and Scheme 5). The recently recognized synthetic versatility of these donor/acceptor-substituted cyclopropanes i 2,io3) (precursors of 1,4-dicarbonyl and P, 7-unsaturated carbonyl compounds, 4-oxocarboxylic acids and esters, among others) gave rise to the synthesis of a large number of such systems with a broad variation of substituents p-acetoxycyclopropanecarboxylates , p-alkoxy- or p-aryloxysubstituted cyclopropanecarboxylates 2-alkoxy-1-methyl-1-cy-... 

Photo-oxidative decarboxylation of indole-3-acetic acid in the presence of pyrimido[5,4-g]pteridine W-oxide has been described. Photoelimination of carbon dioxide has been observed in a variety of esters including aromatic esters, substituted l-naphthylmethyl alkanoates and ethyl a-oxocarboxylates,and is one pathway described in a review of the photochemistry of 2(3H)- and 2(5H) furanones.Ethylene, ethanol and carbon dioxide are the only... 

The ligand-free palladium-catalysed coupling of aryl iodides and bromides with potassium oxalate monoester results in a decarboxylation reaction yielding aromatic esters such as (112). Carbon-hydrogen substitution is involved in the decarboxylative acylation reaction of cyclic enamides with a-oxocarboxylic acids, which may yield acylated enamides such as (114). The reaction is likely to involve a cyclic vinylpalladium intermediate (113) which, after decarboxylation and reductive elimination yields the acylated product. ... 

Lawson, A.M., Chalmers, R.A. and Watts, R.W.E. (1974b), Studies of O-substituted oxime-trimethylsilyl ester derivatives of some metabolically important oxocarboxylic acid,s. Biomed. Mass Spectrom.y 1,199. 

Substituted indoles are of biological interest and are not readily synthesized by conventional methods of indole chemistry. Annulation of a nuclear methyl and an a-ethoxyimine (or an imidate) under basic conditions is a promising procedure. The pyridine oxide ester (87.1) may be converted in high yields into two kinds of pyrrole carboxylic ester the potassium salt of the imidate, on heating in DMF, gives the 3-(2-oxocarboxylate) whereas dilute mineral acid leads to the 2-carboxylate ester. 

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