Methyl ketone, from acids, malonate

Pyrrole- and indole-carboxylic acid chlorides react with dialkyl- and diaryl-cadmium to yield the ketones and it is noteworthy that the reaction of the anhydride of indole-2,3-dicarboxylic acid with diphenylcadmium produces 3-benzoylindole-2-carboxylic acid and not its isomer (53JCS1889). The ability of l-methylindole-2-carboxylic acid to react with nucleophiles is enhanced by conversion into the mixed anhydride with methanesulfonic acid. The mixed anhydride reacts with carbanions derived from diethyl malonate and from methyl acetate to yield the indolyl (3- keto esters (80TL1957). 

Esters, amides, and primary alcohols are obtained from benzo[6]-thiophene carboxylic acids by standard procedures.337 481,585 692 093,695 Acid chlorides undergo the Arndt-Eistert reaction,337,568,689 react with diethyl ethoxymagnesium malonate to give the corresponding methyl ketone,144 557 and are reduced to the aldehyde with 1 ithium tri-ferf-butoxy aluminohydride.33 7... 

In the malonic ester synthesis this enolate ion is alkylated in the same manner as in the acetoacetic ester synthesis. Saponification of the alkylated diester produces a diacid. The carbonyl group of either of the acid groups is at the /3-position relative to the other acid group. Therefore, when the diacid is heated, carbon dioxide is lost in the same manner as in the acetoacetic ester synthesis. The difference is that the product is a carboxylic acid in the malonic ester synthesis rather than the methyl ketone that is produced in the acetoacetic ester synthesis. The loss of carbon dioxide from a substituted malonic acid to produce a monoacid is illustrated in the following equation ... 

The only difference between the acetoacetic ester synthesis and the malonic ester synthesis is the use of acetoacetic ester rather than malonic ester as the starting material. The difference in starting material causes the product of the acetoacetic ester synthesis to be a methyl ketone rather than a carboxylic acid. The carbonyl group of the methyl ketone and the carbon atoms on either side of it come from acetoacetic ester, and the rest of the ketone comes from the alkyl halide used in the second step of the reaction. 

A. N. Dey (174) has described an independent synthesis of the alkaloids. Michael condensation of ethyl 7-ethoxy- or 7-phenoxy-crotonate (LI, R = OEt, R = Et or Ph) with ethyl malonate or cyan-acetate, followed by ethylation and hydrolysis, furnished a mixture of the two racemic forms of the glutaric acid, LII, which were separated by virtue of their different ease of anhydride formation. On treatment with hydrobromic acid, they gave rise to dl-homopilopic acid and dl-homo-isopilopic acid (LIII, R = OH), respectively. Corresponding methyl ketones (LIII, R = Me) were obtained by a similar synthesis from... 

Solid-phase synthesis is of importance in combinatorial chemistry. As already mentioned RuH2(PPh3)4 catalyst can be used as an alternative to the conventional Lewis acid or base catalyst. When one uses polymer-supported cyanoacetate 37, which can be readily obtained from the commercially available polystyrene Wang resin and cyanoacetic acid, the ruthenium-catalyzed Knoevenagel and Michael reactions can be performed successively [27]. The effectiveness of this reaction is demonstrated by the sequential four-component reaction on solid phase as shown in Scheme 11 [27]. The ruthenium-catalyzed condensation of 37 with propanal and subsequent addition of diethyl malonate and methyl vinyl ketone in TH F at 50 °C gave the adduct 40 diastereoselectively in 40 % yield (de= 90 10). 

The cation radical intermediates formed from the enamines may be trapped by nucleophiles other than the solvent when these nucleophiles are electrochemically less oxidizable than the enamines. Indeed, the cation radical intermediates formed from morpholino-, piperidino-and pyrrolidinoenamines are trapped by carbanions derived from active methylene compounds such as methyl acetoacetate, acetylacetone and dimethyl malonate with moderate yields (equation 2)3. The products are easily transformed to the corresponding a-substituted ketones by hydrolysis with dilute hydrochloric acid. 

Pyrazolo[3,4-Z)]pyridines, the 7-chloro-6-fluoro-2,4-dimethylquinoline and its mercapto-thiadiazolyl or oxadiazolyl quinolines 21 were prepared via Diels-Alder reaction conversion of methyl 2-(3-oxo-3-phenylpropenylamino)benzoate into 3-benzoyl-l.S -quinolin-4-one 22 . A mixture of aniline derivatives and malonic ester gave a variety of 3-aryl-4-hydroxyquinolin-2(l//)-ones 23. Condensation of isatins with ketones afforded quinoline-4-carboxylic acids. 2-Aryl-l,2,3,4-tetrahydro-4-quinolinones 22 and carbazolylquinolone were also prepared. The substitution of 2-chloroquinoline gave the 2-substituted quinolines. Basic alumina has catalyzed the C-C bond formation between 2-hydroxy-1,4-naphthoquinone and 2-chloroquinoline derivative to give 21. Reaction of organic halides with 8-hydroxyquinolines gave the respective ethers. The azodye derivatives of 21 were prepared in the absence of solvent. Silica gel catalyzed the formation of 2-ketomethylquinolines from reaction of 2-methylquinolines with acyl chlorides. 

PhSSPh with retention/ or photochemically/ Methyl phenyl N-methyl-sulphoximide gives adducts with ketones after conversion into its carban-ion, from which either tertiary alcohols are obtained by Al-Hg reduction under neutral conditions, or alkenes by reduction in aqueous acid, thus providing an alternative to the Wittig methylenation reaction/ Oxosul-phonium ylides formed by N-dimethylation followed by carbanion formation with NaH are useful as alkylidene-transfer reagents/ Uses of sulphoximides in heterocyclic synthesis have been reported methyl phenyl sulphoximide reacts through N with ethoxymethylene malonate esters. ... 

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