Methyl stearic acid

EXAMPLE 3.14 Branching can also affect melting temperatnre e.g., 10-methyl stearic acid (Fig. 3-16) melts at only 10°C (Compare with Table 3-7). 

Another common branched chain fatty acid is 10-methyl stearic acid, tuberculostearic acid, a major component of the fatty acids of Mycobacterium phlei. In this case, the methyl group originates from the methyl donor 5-adenosyl methionine, while the acceptor is oleate esterified in a phospholipid. This is an example, therefore, of fatty acid modification taking place while the acid is in an O-ester rather than the 5-esters of CoA or ACP. The formation of tuberculostearic acid takes place in two steps the intermediate being 10-methylene stearic acid which is then reduced to 10-methyl stearic acid (Figure 3.9). 

The other peaks demonstrate the power of NMR to identify and quantitate all the components of a sample. This is very important for die phannaceutical industry. Most of the peaks, including a small one accidentally underlying the methyl resonance of paracetamol, arise from stearic acid, which is connnonly added to paracetamol tablets to aid absorption. The integrals show diat it is present in a molar proportion of about 2%. The broader peak at 3.4 ppm is from water, present because no attempt was made to dry the sample. Such peaks may be identified either by adding fiirther amounts of the suspected substance, or by the more fiindamental methods to be outlined below. If the sample were less concentrated, then it would also be... 

Bisamides. Methylenebisamides are prepared by the reaction of the primary fatty amide and formaldehyde in the presence of an acid catalyst. AijAT-Methylenebisoleamide has been made via this route without the use of refluxing solvent (55). Polymethylenebisamides can be made from fatty acid, esters, or acid haUdes with diamines while producing water, alcohol, or mineral acid by-products. Eatty acids and diamines, typically ethylenediamine, have been condensed in the presence of NaBH and NaH2P02 to yield bisamides (56). When stearic acid, ethylenediamine, and methyl acetate react for 6 h at... 

In a series of organic acids of similar type, not much tendency exists for one acid to be more reactive than another. For example, in the replacement of stearic acid in methyl stearate by acetic acid, the equilibrium constant is 1.0. However, acidolysis in formic acid is usually much faster than in acetic acid, due to higher acidity and better ionizing properties of the former (115). Branched-chain acids, and some aromatic acids, especially stericaHy hindered acids such as ortho-substituted benzoic acids, would be expected to be less active in replacing other acids. Mixtures of esters are obtained when acidolysis is carried out without forcing the replacement to completion by removing one of the products. The acidolysis equilibrium and mechanism are discussed in detail in Reference 115. 

A similar reaction occurs with fatty acids (such as stearic acid) or methyl stearate, which undergo isomerization, cracking, dimerization, and oligomerization reactions. This has been used to convert solid stearic acid into the more valuable liquid isostearic acid [102] (Scheme 5.1-70). The isomerization and dimerization of oleic acid and methyl oleate have also been found to occur in chloroaluminate(III) ionic liquids [103]. 

A soap-based powder can be produced in combination with ester sulfonates. Thirty-five percent of a sodium soap mixture (5% lauric acid, 5% myristic acid, 52% palmitic acid, 21% stearic acid, 12% oleic acid, and 5% linoleic acid) is mixed with 15% sodium a-sulfo palm oil fatty acid methyl ester, 3% lauric acid ethoxylate, 5% sodium silicate, 17% sodium carbonate, 20% Na2S04- 10H2O, and 5% water [79]. 

Butyl cellosolve stearate Diamyl naphthalene Dibutyl tin laurate Dioctylphthalate Methyl cellosolve oleate Methyl phthalylethylglycola Phenylsalicylate Propylene stearate Stearic acid... 

As anticipated, SA conversion increases with increasing residence time (1/LHSV) and with increasing temperature to a maximum of about 98%. This limit is most likely caused by equihbrium. This limit and thus the equilibrium constant were not affected by the temperature range studied, consistent with a low heat of reaction. The sum of the molar heats of combustion of stearic acid (11320 kJ/mol) and methanol (720 kJ/mol) is almost the same as the heat of combustion of methyl stearate (12010 kJ/mol), meaning that the change in enthalpy of this reaction is nearly zero and that the equihbrium constant is essentially temperature independent. 

In order to obtain stearone with the highest melting point, the checkers found it necessary to purify the above recrystallized stearic acid by converting it to the methyl ester and fractionat-... 

Egg yolk TMAH Palmitic and stearic acids methyl esters (>60%) azelaic acid methyl esters (<10%) and pyrrole (<50%) 1... 

Figure 12.12 THM GC/MS curves of a Winsor Newton lemon alkyd paint (a) and of an alkyd sample taken from Fontana s work Concetto spaziale (1961) (b). Peak assignments 1, 1,3 dimethoxy 2 propanol 2, 1,2,3 trimethoxy propane 3, 3 methoxy 1,2 propandiol 4, 4 chloro benzenamine 5, 3 methoxy 2,2 bis(methoxymethyl) 1 propanol 6, 3 chloro N methyl benzenamine 7, 3 methoxy 2 methoxymethyl 1 propanol 8, 4 chloro N methyl benzenamine 9, phthalic anhydride 10, 3 chloro 4 methoxy benzenamine 11, suberic acid dimethyl ester 12, dimethyl phthalate 13, azelaic acid dimethyl ester 14, sebacic acid dimethyl ester 15, palmitic acid methyl ester 16, oleic acid methyl ester 17, stearic acid methyl ester 18, 12 hydroxy stearic acid methyl ester 19, 12 methoxy stearic acid methyl ester 20, styrene 21, 2 (2 methoxyethoxy) ethanol 22, 1,1 oxybis(2 methoxy ethane) 23, benzoic acid methyl ester 24, adipic acid dimethyl ester 25, hexadecenoic acid methyl ester 26, dihydroisopimaric acid methyl ester 27, dehydroabietic acid methyl ester 28, 4 epidehydroabietol...

Sodium >-toluenesulfinate dihydrate, 34, 93 Sommelet reaction, 33, 93 Sorbic acid, 5-hydroxy-0-methyl, 5-lactone, 32, 57 Stannic chloride, 33, 91 Stearic acid, 34, 15 Stearolic acid, 37, 77 Stearone, 33, 84 cis-Stilbene, 33, 88 Irans-Stilbene, 33, 89... 

TLC spots with marker reveal the presence of free fatty acids (FFA), diglyceride (DG), monoglyceride (MG) but negligible amount of TG. GCMS of fatty acid— methyl esters (FAME) from lion mane presented evidence for fatty acids ranging from C9-C24 (Figs. 5.3- 5.6). Low volatility molecules like nonanedioic acid (Fig. 5.3), tridecanoic acid (Fig. 5.4), 12-methyl tridecanoic acid were also present in lion hair lipids. In addition fatty acids such as myristic, pentadecanoic, palmitic, heptanoic, stearic and octadecenoic acids (Fig. 5.5) have also been detected. Erucic... 

The solubility of C60 and C70 in a series of vegetable oils, namely olive, sunflower, peanut, soybean, linseed and castor oil, has been determined quantitatively spectrophotometrically. Additionally, the solubility of C60 and C70 has been determined quantitatively in the methyl esters of brassica oilseed and only qualitatively in molten cow butter, molten stearic acid and molten behenamide. The experimental results show that the solubility of fullerenes appears to be dependent on the unsaturation level of the fatty acids composing the vegetable oils being lower in oils with higher unsaturation level. The solubility has been found dependent also on the polarizability parameter of the vegetable oils. 

The GC/MS study of methylated fulvic acid showed the presence of -hydroxybenzoic acid (ff 166), vanillic acid (Nr " 196), a methyldihydroxybenzoic acid (M " 210), coumaric acid (M+ 192), syringic acid (M" " 226), caffeic acid (fT " 222), ferulic acid (M" " 222), and stearic acid (M" " 298). The same compounds were present in humic acid, along with palmitic acid (M" " 270). The presence of these compounds was confirmed by TLC, using standard compounds. 

In another paper from the Jackson Laboratories of the du Pont Company (Calcott et al., 34) there is reported a repetition of some of the reactions of Simons and Archer, as well as additional ones. Mono-, di-, and 1,2,4,5 tetraisopropylbenzene were obtained from propylene and benzene both l -chloro-i-butylbenzene and di-(l/-chloro)-d-butylben-zene were obtained from 3-chloro-2-methyl-propene-l and benzene p-f-butyltoluene and di-i-butyltoluene were obtained from diisobutylene and toluene tetraisopropylnaphthalene was obtained from propylene and naphthalene naphthyl-stearic acid was obtained from oleic acid and naphthalene mixed isopropyltetrahydronaphthalene was obtained from propylene and tetrahydronaphthalene 2,4,6-triisopropylphenol was obtained from propylene and phenol a mixture of monoisopropylated m-cresols was obtained from propylene and wi-cresol and di-(s-hexyl)-diphenyl oxide was obtained from hexene-3 and diphenyl oxide. 

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