Dicarboxylic ketocarboxylic acid

Complex mixtures of oxidized products are produced in the ozonolysis of BaP on solid substrates. For example, BaP deposited on a glass fiber filter and exposed to 1 ppm 03 in air primarily formed products characteristic of the ring-opening mechanism, e.g., dialdehydes and dicarboxylic and ketocarboxylic acids. However, some quinones and phenols, were also formed. For details on the mechanisms and O-PAH products of these BaP-Ov gas-solid substrate reactions, see Van Cauwenberghe et al. (1979) and Van Cauwenberghe and Van Vaeck (1983 and references therein). 

Tedetti, M., K. Kawamura, B. Charriere, N. Chevalier, and R. Sempere. 2006. Determination of low molecular weight dicarboxylic and ketocarboxylic acids in seawater samples. Anal. Chem. 78 6012-6018. 

Cyclic ketones also can be cleaved by oxidation with KMn04 (Figure 17.33). Under these conditions, 1, -ketocarboxylic acids or 1, -dicarboxylic acids are formed. The mechanism of this reaction is not known in detail. It is known only that KMn04 serves as a three-electron oxidizing reagent and that it is reduced to Mn02. 

Keto-y-dicarboxylic acid esters from fi-ketocarboxylic acid esters s. 4, 770 ... 

Ketocarboxylic acids from dicarboxylic acid anhydrides... 

Figure 3.9 Typical capillary gas chromatogram of the derivatives of dicarboxylic acids (C2 Cg), ketocarboxylic acids ( C0C2, C0C4, pyruvic acid), and dicarbonyl (glyoxal) isolated from sea water (Sample collected in the Bay of Marseille (northwestern Mediterranean Sea) in September 2005. Reprinted with permission from Determination of low molecular weight dicarboxylic and ketocarboxylic acids in seawater sample) Tedetti, M, et ai, Analytical Chemistry (1 Sep 2006), 78 ( 7), 6012-6018. Copyright (2006) American Chemical Society).

In summary, carboxylic acids with a carbonyl group at the 3-position (both i8-ketocarboxylic acids and 8-dicarboxylic acids) lose CO2 when they are heated. 

Under different reaction conditions, vicinal diol production [70] or C=C double bond oxidative cleavage to carboxylic acids occurs [59, 71], Dialdehydes are produced from cycloolefins, by tungstic acid as catalyst in t-butanol [72], Secondary alcohols yield ketones, while primary alcohols produce aldehydes or carboxylic acids [59, 68-69, 73-74], Different products are obtained from glycols, under different reaction conditions, 1,2-Diols are cleaved to ketocarboxylic acids and dicarboxylic acids [58, 75], or oxidised to a-hydroxy ketones [76], The latter can be obtained directly from the olefins, with lower selectivity [77], Lactones are formed by 1,4-diols and other a,o)-diols [78], Internal alkynes predominantly yield a,p-epoxyketones [79], or 1,2-diketones and carboxylic acids if HgfAcO) is added as the cocatalyst [80], Terminal alkynes yield a-ketoaldehydes and carboxylic acids. 

Among many classes of organic compounds the best results were obtained with the following combination a dihydrojg -dicarboxylic acid as modifier and a fteto-ketocarboxylic acid ester (or Z>era-diketone) as substrate. 

Distributions of water-soluble dicarboxylic acids, ketocarboxylic acids and dicarbonyls... 

Fig. 9. Representative chemical structures of dicarboxylic acids, ketocarboxylic acids and a-dicarbonyls detected in the aerosol samples collected from Jeju Island.

Sodium hydride C-Acylation with diacylamines Ketocarboxylic acid amides from dicarboxylic acid imides... 

Sol 1. (c) Geminal dicarboxylic acid (i.e., compounds in which the two carboxyl groups are on the same carbon atom) and p-ketocarboxylic acid obtained by the oxidation of diols II and IV, respectively, readily undergo decarboxylation on heating. 

Li, Y.-C. Yu, J.Z. Simultaneous determination of mono- and dicarboxylic acids, omega-Oxo-carboxyUc acids, midchain ketocarboxylic acids, and aldehydes in atmospheric aerosol samples. Environ. Sci. Technol. 2005, 39, 7616-7624. 

Ketocarboxylic acid esters from dicarboxylic acid chloride esters s. 17, 878... 

Cyclic ketocarboxylic acids from dicarboxylic acids... 

Titanium tetrachloride 3-Hydroxyethers from acetals by rearrangement s. 17, 790 o-Phenolketones from phenolesters Fries rearrangement s. 19, 798 Poly phosphoric acid Cyclic ketocarboxylic acids from dicarboxylic acid anhydrides s, 19,961... 

Kawamura K, Watanabe T (2004) Determinatitm of stable carbon isotopic compositions of low molecular weight dicarboxylic acids and ketocarboxylic acids in atmospheric aerosol and snow samples. Anal Chem 76 5762... 

Ketocarboxylic acid esters from -keto-/ -dicarboxylic acid esters... 

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