Carboxylic acids, preparation

A number of (R)-thiazolidine-4-carboxylic acids prepared from cysteine and various aldehydes have been investigated [138 - 140], Nonenzymatic hy-... 

As shown in Figure 13.2.2, the top peak of the excitation spectra of the ZnS Mn without carboxylic acid prepared in this method shifts toward higher energy by 0.06 eV, to 3.67 eV (339 nm) from 3.61 eV (344 nm), for the particles prepared by a conventional method, with their average particle size being 0.5 mm. By preparing them in the presence of AA, however, a larger blue shift by 0.16 eV with respect to the commercial particles, to 3.77 eV (330 nm), is observed. 

Reduction of carboxylic acids preparation of primary alcohols... 

The methyl ester has also been obtained by esterification of cyclopentanecarboxylic acid.8 The acid, in turn, has been prepared by the Favorskii rearrangement,6 7 9-11 by the reaction of cyclopentyl Grignard reagent with carbon dioxide,12 by the carbonylation of cyclopentyl alcohol with nickel carbonyl13 or with formic acid in the presence of sulfuric acid,14 and by the hydrogenation of cyclopentene-1-carboxylic acid prepared from ethyl cyclopentanone-2-carboxylate 15 or from cyclopentanone cyanohydrin.16... 

Fmoc-EALAKA-Rink-resin (1.25 equiv) was allowed to swell in DMF (1.5 mL) for 1 h. The DMF was removed by filtration and the resin washed with additional DMF (1.5 mL). The resin was then treated with 20% piperidine/DMF (2 x 1.5 mL) for 10 min to remove the Fmoc protecting group, filtered, and washed with additional DMF (10 x 1.5 mL). A soln of the carboxylic acid prepared above, EDC (1 equiv), and HOBt (1 equiv) in DMF (1.5 mL) was added to the resin and the slurry was stirred for 1 h. The resin was filtered, washed with DMF (2 x 1.5 mL) followed by CH2Q2 (2 x 1.5 mL), and stored in vacuo overnight. 

Diphenylphosphinoferrocenecarboxylic acid, in Rh carbonyl complexes, 7, 133 l,l -Diphenylphosphinoferrocene carboxylic acid, preparation, 6, 200... 

Heuma nn II Process. In the Heumann II process, starting from anthranilic acid,, V-phcnylglycine-o-carboxylic acid, prepared from anthranilic acid and chloroace-tic acid, is added in the form of the alkali metal salt 13 to a KOH/NaOH melt at 200 °C to produce indoxylcarboxylic acid salt 14. After hydrolysis and decarboxylation, the product is oxidized in air to yield indigo [19],... 

For example, an aldehyde prepared by the oxidation of a primary alcohol (Sec. 16.8) may very well be contaminated with the carboxylic acid this acid can be simply washed out with dilute aqueous base. The carboxylic acid prepared by oxidation of an alkylbenzene (Sec. 12.10) may very well be contaminated with unreacted starting material the carboxylic acid can be taken into solution by aqueous base, separated from the insoluble hydrocarbon, and regenerated by addition of mineral acid. 

Table S Carboxylic Acids Prepared from Ketones ...

Table 5 Carboxylic Acids Prepared from Ketones25...

Trifluoroacetic and triflic anhydrides can be utilized to promote acylation of aromatics with carboxylic acids without any metal catalyst. Thus, the trifluoroacetic anhydride (TFAA)-promoted cycloacylation of conveniently functionalized carboxylic acids prepared from Baylis-Hillman adducts... 

Oxidative decarboxylation. Dianions of carboxylic acids (prepared with LDA) react with O2 in ether at -78° to form a-hydroperoxy acids. These need not be isolated when DMF dimethyl acetal or an acid is added at room temperature, carbon dioxide is lost with formation of a carbonyl compound. 

Reactions Involving Carboxylic Acids Preparation of Carboxylic Acids... 

In the Hunsdiecker reaction, the silver salt of a carboxylic acid, prepared by treating the acid with silver oxide, is treated with a halogen. Bromine is the usual reagent, but iodine may also be used. Carbon dioxide is evolved and the corresponding alkyl halide is obtained, usually in fair to good yield. 

Deoxymugineic acid (295), a third constituent of Avena sativa, is prepar H K animation of 348 with amine diester 358 (58% yield). Compound 358 is in turn reductive amination of 353 with L-azetidine-2-carboxylic acid. prepared by... 

The first reaction shown in the passage described the synthesis of a carboxylic acid (2,2-dimethyl-4-phenylbutanoic acid) in which the a carbon is quaternary. What is the maximum degree of substitution at the a carbon of a carboxylic acid prepared by the malonic ester synthesis ... 

The silatrane derivative Ph2P(=S)OSi(OCH2CH2)3N shows N->Si to be 206 pm, silatrane 4-carboxylic acids prepared using L-N,N-bis(2-hydroxyethyl)-serine or -threonine with N- Si... 

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