Organic butyric acid

Hence one extraction with 100 ml. of benzene removes 3 0 g. (or 75 per cent.) of the n-butyric acid, whilst three extractions remove 3 5 g. (or 87-5 per cent.) of the total acid. This clearly shows the greater efficiency of extraction obtainable with several extractions when the total volume of solvent is the same. Moreover, the smaller the distribution coefficient between the organic solvent and the water, the larger the number of extractions that will be necessary. 

It IS hard to find a class of compounds in which the common names of its members have influenced organic nomenclature more than carboxylic acids Not only are the common names of carboxylic acids themselves abundant and widely used but the names of many other compounds are derived from them Benzene took its name from benzoic acid and propane from propionic acid not the other way around The name butane comes from butyric acid present m rancid butter The common names of most aldehydes are derived from the common names of carboxylic acids—valeraldehyde from valeric acid for exam pie Many carboxylic acids are better known by common names than by their systematic ones and the framers of the lUPAC rules have taken a liberal view toward accepting these common names as permissible alternatives to the systematic ones Table 19 1 lists both common and systematic names for a number of important carboxylic acids... 

Oxidation of butyraldehyde to butyric acid [107-92-6]is most commonly carried out employing air or oxygen as the oxidant. Alternatively, organic oxidants, eg, cumene hydroperoxide, can also be employed effectively to give high yields of butyric acid, (4). 

In isolating higher-melting compounds prepared by this method (e.g., 7-naphthylbutyric acids), the layers are separated after cooling to 50-60°, benzene is used for the extraction, and the combined solution is clarified with Norite while still wet, concentrated somewhat, and allowed to cool for crystallization. In preparing methoxylated adds such as 7-anisyl- or 7-veratryl-butyric acid some demethylation occurs and a modification is necessary. The toluene layer and extracts are mixed with an excess of dilute sodium hydroxide and the organic solvents are... 

In addition to the twenty amino acids commonly found in proteins, two others—selenocysteine and pyrrolysine—are found in some organisms, and more than 700 nonprotein amino acids are also found in nature. y-Amino-butyric acid (GABA), for instance, is found in the brain and acts as a neurotransmitter homocysteine is found in blood and is linked to coronary heart disease and thyroxine is found in the thyroid gland, where it acts as a hormone. 

Esterifications Investigated in Micro Reactors Organic synthesis 19 [OS 29] Esterification of 4-(1-pyrenyl)butyric acid... 

When comparing the dust-borne concentrations of butyric acid and p-cresol with the odour thresholds it seems that the concentrations are too small to be relevant for an odour nuisance. However, if the dust is removed from the gas phase of the air from animal houses the odour disappears (39), (40), (14). This supports the opinion of HAMMOND et al. (40) that the odor is concentrated on the dust particles. The authors conclude from their data that the concentration of the two odorants butyric acid and p-cresol is about 4TO7 greater on an aerosol particle than it is in an equal volume of air. Thus, an aerosol particle deposited on the olfactory organ carries odour equivalent to a much greater volume of air (40). These considerations indicate that dust from animal houses should be taken into account in connection with odour emission/immission measurements not only by chemical analysis but by sensory evaluations using olfactometers without dustfilters, as well. 

It may be stated at this point that the presence of a /3-hydroxy-butyrate fat in certain organisms is a matter of general biochemical importance. Usually /3-hydroxybutyric acid and the acetone bodies are derived from n-butyric acid directly. The unambiguous formation of jS-hydroxybutyric acid anhydrides from carbohydrates opens up new vistas its formation from acetaldehyde, and from pyruvic acid, through aldol intermediates can be understood without difficulty. Kirrmann s reaction, to which little attention has been paid, is at the same time an example of an oxygen shift, leading from hydroxyaldehydes to fatty acids. 

When sugar that is produced by the Scholler process is fermented by the acid-producing organism, the yield is only 35% of the total sugar. If the solution is first fermented by yeast, however, a 37 % yield of alcohol is produced, and from the residual liquor fermented by the butyric acid organism, a 15.5% yield of acids is produced, making a total recovery of 52.5%. 

Fig. 8.5. HPLC chromatogram of a first-out silage juice using a Rezex ROA-organic acid column. Identity a, laotio aoid b, formic acid c, acetic acid d, propionic acid e, n-butyric acid f, 2-ethylbutyric acid (internal standard).

Problem 16.70 Use isopropyl alcohol as the only organic compound to synthesize (a) a-hydroxyisobutyric acid, (h) /3-hydroxy butyric acid. 

Organic Acids Acetic Acid Butyric Acid Formic Acid Propionic Acid Acrylic Acid (inhibited)... 

The situation is summarized from a slightly different perspective in Figure 2.2. Here, data obtained using the same set of organic solvents have been plotted. The porcine pancreatic lipase-catalyzed transesterification of sulcatol (6-methyl-5-hepten-2-ol) with butyric acid trifluoroethyl ester [81] has been chosen (arbitrarily) to calibrate the solvents. It is clear that, irrespective of the solvent descriptors that one may aim to investigate, different systems are seen to respond differently to the same (change of) medium. 

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