Fatty acid preparation

Specifically MSA has been found to be more effective than -toluenesulfonic acid and sulfuric acid in preparing dioctyl phthalate (405). A U.S. patent also discloses its use to prepare light-colored fatty esters (406). It is also important as a catalyst to prepare acrylates, methacrylates, adipates, phthalates, trimeUitates, thioglycolates, and other esters. 

Fatty acids are prepared by acylating thiophene with acid chlorides and reducing the ketones (218) to alkylthiophenes according to Wolff-Kishner or Clemmensen. The latter are then acetylated and oxidized by hypochlorite to 5-alkyl-2-thiophenecarboxylic acids, > ... 

The development of monoalkyl phosphate as a low skin irritating anionic surfactant is accented in a review with 30 references on monoalkyl phosphate salts, including surface-active properties, cutaneous effects, and applications to paste and liquid-type skin cleansers, and also phosphorylation reactions from the viewpoint of industrial production [26]. Amine salts of acrylate ester polymers, which are physiologically acceptable and useful as surfactants, are prepared by transesterification of alkyl acrylate polymers with 4-morpholinethanol or the alkanolamines and fatty alcohols or alkoxylated alkylphenols, and neutralizing with carboxylic or phosphoric acid. The polymer salt was used as an emulsifying agent for oils and waxes [70]. Preparation of pharmaceutical liposomes with surfactants derived from phosphoric acid is described in [279]. Lipid bilayer vesicles comprise an anionic or zwitterionic surfactant which when dispersed in H20 at a temperature above the phase transition temperature is in a micellar phase and a second lipid which is a single-chain fatty acid, fatty acid ester, or fatty alcohol which is in an emulsion phase, and cholesterol or a derivative. 

These emulsifiers are prepared from sucrose and edible fatty acids. The primary hydroxyl groups of the sucrose are esterified by the fatty acid. In Figure 2, R is the alkyl group of the fatty acid. Fatty acids can be reacted with one, two or three primary hydroxyl groups to yield mono, di or triesters, respectively. 

Regarding the interference of lipids and fatty acids in preparation of LPC, Nagy et al. (15) made an extensive study of this problem and determined, as indicated in Table VII, that the lipid content and total lipid distribution in some green protein fractions is indeed significant and can present a problem with protein extractability and purification. They indicated however, most of the lipid appeared to come from extraction of cell walls and ruptured cellular contents during the maceration process. 

Experiment.—Dissolve 0-4 g. of the acetic acid-desoxycholic acid compound, prepared as above, in 4 c.c. of 2A-sodium hydroxide. Prepare also from about 100 mg. of the fatty acids isolated, by boiling with a few cubic centimetres of dilute sodium hydroxide solution, a soap solution and cool it till it sets to a jelly. Add part of the solution of desoxycholic-acetic acid. The soap dissolves. 

Ci6j Cjg saturated fatty acids, Armak Industrial Chemicals Division (Chicago, IL) oleic acid, A. Gross Company (Newark, NJ) elaidic acid, laboratory preparation (12) tallow, Corenco Corporation (Philadelphia, PA) (titer, t =... 

HPLC has more or less supplanted GC as a method for quantifying drugs in pharmaceutical preparations. Many of the literature references to quantitative GC assays are thus old and the precision which is reported in these papers is difficult to evaluate based on the measurement of peak heights or manual integration. It is more difficult to achieve good precision in GC analysis than in HPLC analysis and the main sources of imprecision are the mode of sample introduction, which is best controlled by an autosampler, and the small volume of sample injected. However, it is possible to achieve levels of precision similar to those achieved using HPLC methods. For certain compounds that lack chromophores, which are required for detection in commonly used HPLC methods, quantitative GC may be the method of choice, for analysis of many amino acids, fatty acids, and sugars. There are a number... 

Butyric acid is one of the simplest fatty acids. Fatty acids, which are the building units of fats and oils, are natural compounds of carbon chains with a carboxyl group (-COOH) at one end. Most natural fatty acids have an unbranched carbon chain and contain an even number of carbon atoms because during biosynthesis they are built in two carbon units from acetyl coenzyme A (CoA). Butyric acid is an unsaturated fatty acid, which means all carbon-carbon bonds are single bonds. Common names for fatty acids stem from their natural sources. In addition to butyric acid, some other common saturated fatty acids include lauric acid, palmitic acid, and stearic acid. Lauric acid was first discovered in Lauraceae (Laurus nobilis) seeds, palmitic oil was prepared from palm oil, and stearic acid was discovered in animal fat and gets its name from the Greek word stear for tallow. 

Composition. Crystals deposited from ethanol solution as well-formed thin plates. The fatty acid content of the crystals is given in Table I. For all chain lengths the acid content approximates closely that required for 1 to 1 stoichiometry. This is also the case for most of the acid-soaps prepared by the petroleum ether route the low values of titratable acid in some instances are ascribable to the presence of free soap. 

Table II lists the absorption peaks observed in the 6-micron region for the acid-soaps. With the exception of potassium acid-butyrate all members up to Ci2 have their major absorption peak (underlined in Table II) at 5.82 to 5.9 microns. On the other hand, the acid-soaps of chain length Ci4 or greater have their major C=0 absorption band at 6.1 microns. A sole exception in Table II is the potassium acid-stearate prepared from Eastman fatty acid, whose major absorption peak falls in the range 5.82 to 5.9 microns again.

Clinical Chemistry (see Chapter 10). Gas chromatography is adaptable to such samples as blood, urine, and/or biological fluids. Compounds such as proteins, carbohydrates, amino acids, fatty acids, steroids, triglycerides, vitamins, and barbiturates are handled by this technique, directly or after preparation of appropriate volatile derivatives. 

Again, as all these acids have two carboxyls attached to the same carbon atom, they lose carbon dioxide on heating and pass into monobasic fatty acids (B., 27, 1177). This affords an important and standard synthesis for these latter acids (see Preparation 427, also Preparation 60 and p. 113). 

Reaction XLVm. (a) Action of Alkali Cyanides on Alkyl and Acyl Halides. (Bl., [2], 50, 214.)—This reaction is capable of very wide application, all the simple alkyl halogen compounds, the acyl halides, and the halogen fatty acids come within its scope. The nitriles so formed yield acids by hydrolysis, so it is frequently the first step in the synthesis of an acid—the preparation and hydrolysis of the nitrile are often combined. The preparations of malonic, succinic, tricarballylic and other acids (Preparations 60, 61, 62) illustrate this. The extension of this reaction to acyl halides is important, and should be referred to, as should the interaction of silver cyanide, and alkyl iodides, to give isonitriles. Mercuric and silver cyanides, it may be noted, give with acyl chlorides and bromides better yields of normal acyl nitriles than do the alkali cyanides. 

Figure 2 presents the effect of the various volumetric ratios of water to rapeseed oil on the yield of fatty acids as prepared with both flow- and batch-type reaction systems at 270°C for 20 min. The volumetric ratios of 1/4 and 4 correspond to the molar ratios of 13 and 217, respectively. For the batch-type system, the hydrolysis rate of triglycerides seemed to be affected more by the amount of water, and a slightly better conversion was seen with the flow-type reaction system. Even though the volumetric ratio of 1/4 is equivalent to the molar ratio of 13 in water, which is theoretically higher than its stoichiometry of 3, the formation of fatty acids in both reaction systems was obviously low. In addition, it was found that at a volumetric ratio less than 2/3, it was difficult to separate hydrolysis products from the water portion that contained glycerol. On the other hand, the presence of water in fatty acids would have a negative effect on the methyl esterification reaction (15). 

Vallejo-Cordoba, B. (1999) Detection of milk fat substitution by applying multivariate analysis to fatty acid derivatives prepared in situ, in Proceedings ofAnnual Meeting of Institute of Food Technology, 1999 (http //confex.com/ift/99annual/abstracts/3794.htm). 

Polyglycerol Polyricinoleic Acid is prepared by esterification of polyglycerol with condensed castor oil fatty acids. The castor oil fatty acids are mainly composed of 80% to 90% ricinoleic acid. It is a clear, light brown, viscous liquid. It is soluble in ether, in hydrocarbons, and in halogenated hydrocarbons. It is insoluble in water and in alcohol. 

C-Acylation. C-Acylation of active methylene compounds is usually conducted under basic conditions. Masamune et al. have developed a new method for conducting this reaction under neutral conditions that is patterned on the enzymic synthesis of fatty acids. The acylating reagent is the imidazolide of a carboxylic acid (1) prepared in situ. The substrate is the neutral magnesium salt of a mono ester or thioester of a malonic acid (2), prepared with magnesium ethoxide. The reaction of 2 with 1 is conducted in THF at 25-35° for 18-24 hours the yield of products (3) is generally >85%. ... 

DAG oil is prepared through the process of enzymatic esterification. Starting with a blend of soybean and canola oils, fatty acids are prepared then mixed... 

The study of monolayers formed on a wafer surface has also provided imporfanf informahon. A fhin film of an amphiphilic (confaining both polar and nonpolar groups) compormd such as a fatty acid is prepared. This is done by depositing a small quantity of the compound dissolved in a volatile solvent on a clean aqueous surface befween fhe barriers of a Langmuir trough (Fig. 8-8). The difference in surface fension (n) across the barriers is measured with a suitable device for differenf areas of the monolayer, i.e., for differenf positions of the moveable barrier. The value of n is low for expanded monolayers and falls to nearly zero when fhe surface is no longer completely covered. The pressure reaches a plateau when a compact mono-layer is formed, after which if rises again (Fig. 8-8B). 

When mixed in equimolar proportions with a fatty acid, such as stearic acid or oleic acid, triethanolamine forms an anionic soap with a pH of about 8, which may be used as an emulsifying agent to produce fine-grained, stable oil-in-water emulsions. Concentrations that are typically used for emulsification are 2-4% v/v of triethanolamine and 2-5 times that of fatty acids. In the case of mineral oils, 5% v/v of triethanolamine will be needed, with an appropriate increase in the amount of fatty acid used. Preparations that contain triethanolamine soaps tend to darken on storage. However, discoloration may be reduced by avoiding exposure to light and contact with metals and metal ions. 

Following the synthetic method described for arachidonylethanolamide, the ethanolamides of the following unsaturated fatty acids were prepared. 

Chapter 10 Fatty Acid Amides Preparation from Common Household Oils... 

---