Carboxylic acids ketocarboxylic acid esters

Ketocarboxylic acids from carboxylic acid ester chlorides... [Pg.228]

J-Ketocarboxylic acid esters from carboxylic acid esters s. 3,638 COCHRCOOR ... [Pg.206]

Carboxylic from malonic esters s. 22, 84 ketones from -ketocarboxylic acid esters s. H. Hagiwara et al., Bull. Chem. Soc. Japan 48, 3723 (1975)... [Pg.36]

Alkali alkoxide / -Ketocarboxylic acid esters from 2 carboxylic acid ester molecules... [Pg.189]

Interchange of acyl groups of j -ketocarboxylic acid esters via jS,fi -dikeio-carboxylic acid esters s. 11, 886... [Pg.253]

Ketones from / -ketocarboxylic acid esters s. 13, 131 nitriles from a-cyano-carboxylic acid esters s. Am. Soc. 81, 5397 (1959)... [Pg.404]

Cyclic j -diketones from ketocarboxylic acid esters. Diethyl a-methyl-a-acetyl-glutarate in dry ether added dropwise with stirring to a suspension of alcohol-free K-ferf-butoxide in dry ether, and refluxed 3 hrs. -> ethyl l-methyl-2,4-dioxocyclohexane-l-carboxylate. Y 70.4%. S. M. Mukherji, R. K. Sharma, and O. P. Vig, Soc. 1958, 4770. [Pg.612]

Typical thermal stabilizers for PVC are organic metal salts and soaps, phosphite, esters, and epoxy compounds. Examples are barium/zinc carboxylates [46], barium/cadmium carboxy-lates [47], calcium/zinc stearate [48], lead stearate [49],organotinmercaptides[50],organotin sulfides, organotin carboxylates[51], among others. Costabilizers such as 1,3-diketones, dihydropyridines, epoxy plasticizers, P-ketocarboxylic acid esters, phenolic antioxidants, a-phenylindols, and phosphates are used to improve the stabilizer s elfectiveness. [Pg.139]

Lithium liq. ammonia Stereospecific reduction C-carboxylation y -Ketocarboxylic acid esters from a,/ -ethyleneketones... [Pg.172]

Selective cathodic reduction Carboxylic from ketocarboxylic acid esters... [Pg.342]

Use of a /3-ketocarboxylic acid derivative may circumvent this problem (8-ketocarboxylic acid derivatives react with esters of a-amino carboxylic acids to give (Y) a-aminonitriles afford (Z) in a condensation step. [Pg.142]

The butylated /3-ketoester C of Figure 10.23 is not the final synthetic target of the acetoacetic ester synthesis of methyl ketones. In that context the /3-ketoester C is converted into the corresponding /3-ketocarboxylic add via add-catalyzed hydrolysis (Figure 10.24 for the mechanism, see Figure 6.19). This /3-ketocarboxylic acid is then heated either in the same pot or after isolation to effect decarboxylation. The /3-ketocarboxylic add de-carboxylates via a cyclic six-membered transition state in which three valence electron pairs are shifted at the same time. The reaction product is an enol, which isomerizes immediately to a ketone in general and to phenyl methyl ketone in the specific example shown. In general, alkyl methyl ketones are obtained by such acetoacetic ester syntheses. [Pg.392]

Amino Acids and Peptides. - Wasserman s method of one-carbon homologation of carboxylic acids to give a-ketocarboxylates involves reaction with cyanomethylenetriphenyl-phosphorane followed by ozone (Scheme 24) and has been used as a key step in a chemo-enzymatic synthesis of isotopically labelled L-valine, L-isoleucine, and o/fo-isoleucine. Alkylation of the carbanion derived from the imino-substituted methylphosphonate diphenyl ester (186) with indol-3-ylmethyl bromide followed by appropriate deprotection has been used to prepare the phosphonate analogue (187) of tryptophan (Scheme 25). The deprotected analogue (188) and derived peptides show activity as inhibitors of chymotrypsin. Two approaches to solid phase Wadsworth-Enunons reactions which have applications in combinatorial chemistry have been reported. In one diethylphosphonoacetamide is bound to PEG-PAL resin via a peptide link, while... [Pg.267]

Figure 1 shows the infrared spectra of the p-ketocarboxylic acid-functionalized poly (IB-PMS) copolymer (middle spectrum) and the ester-functionalized poly (IB-PMS) copolymer (top spectrum). The infrared spectrum of the ester product shows the disappearance of a broad peak at 3500-3100 cm" 1 due to the carboxylic add group and the appearance of new characteristic ester peaks at 1738 cm" and 1718 cm", in addition to the carbonyl peak at 1610 cm"l (Figure 1). This suggests complete conversion of the acid-fiinctionalized polymer to the ester-frmctionaliz(Kl polymer.

Acylation with carboxylic acid esters N-Acylation of j5-ketocarboxylic acid amides C-Acylation of diacylamines... [Pg.371]

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