Methyl oleate

Methyl oleate [112-62-9] M 296.5, f -19.9 , b 217 /16mm, d 0.874, n 1.4522. Purified by fracuonal distn under reduced pressure, and by low temperature crystn from acetone. 

Stork and Takahashi took -glyceraldehyde synthon from the chiral pool and condensed it with methyl oleate, using lithium diisopropyl amide as catalyst for the mixed aldol reaction, leading to The olefinic linkage is a latent form... 

Methyl oleate gives methyl 9,10-dideuterostearate on treatment with deuterium. Similarly, methyl linoleate gives 9,10,12,13-tetradeuterostearate. The products have bp 214-215715 mm. 

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]. 

The addition of an ester sulfonate of an unsaturated fatty acid improves the rinsing properties in washing tests. A mixture of 50% sodium methyl a-sulfostearate and 50% sodium salt of sulfonated methyl oleate (30 70 mono-sulfonate/polysulfonate ratio) was used [83]. 

This has been found to be a general reaction for many types of olefins. It has also been applied to highly branched structures, such as 2,4,4-trimethyl-2-pen-tane and propylene trimers and tetramers [177], to unbranched olefins with internal double bonds, such as methyl oleate [178] and tricosane, and to a-ole-fins [179], In all cases the data indicate that the reaction occurs at the double... 

C HgfC H2)7-C HCI-C H-(C H2)7-C02CH3 FIGURE 1.15 Product of reaction between DDT and methyl oleate. 

Schwack W (1988) Photoinduced additions of pesticides to biomolecules. 2. Model reactions of DDT and methoxychlor with methyl oleate. J Agric Eood Chem 36 645-648. 

In the case of functionalized olefins, heterogeneous catalysts have usually not performed well [84,85]. Methyl oleate is the typical test substrate the following order of stability towards the ester functional group for the different SOM catalysts has been observed (based on the number of turnovers) Re W > Mo, which is similar to what has been described for related homogeneous systems. In the specific case of Re, 900 TON can be reached, while TON for other Re-based heterogeneous catalysts do not exceed 200 [79,84]. 

C12 to C20, primarily Ci6 to ( is), used as surface lubricants in the manufacture of food-contact articles. The method, which uses ethyl palmitate (Eastman Chemicals No. 1575 Red Label) as an internal standard, has been validated at 200 ppm total FAME [185]. Other FAME standards (methyl palmitate, methyl stearate, methyl oleate, methyl linoleate and methyl linolenate) are available (Applied Science Laboratories) [116], Worked out examples of additive determinations are given in the Food Additives Analytical Manual [116], which also describes a great many of indirect food additives, such as BHA, BHT, TBHQ, l-chloro-2-propanol, DLTDP, fatty acid methyl esters, w-heptyl-p-hydroxybenzoate, propyl-gallate, sodium benzoate, sodium stearoyl-2-lactylate, sorbitol and phenolic antioxidants. EPA methods 606 and 8060 describe the CGC separation of phthalate esters (direct injection) (cf. Figure 4.2). 

Q-MG, CLG, DG, Retinue attraction of workers to mated queen QMP,methyl oleate 56, (2 )-3-(4-hydroxy-3-methoxy)-prop-2-en-1 -ol 57, hexadecan-1 -ol 58, linolenic acid 59 [96,99]... 

In the Table 2 the methyl oleate content in the reaction system and the immobilized enzyme activity, towards the transesterification reaction, are reported. 

Recent detailed studies on autoxidation reactions have been published for tetralin 44-46) cumene and ethylbenzene 46,47) methyl oleate 48,49) and benzaldehyde 50h... 

Polar-substituted alkenes where the functionality is not attached to a strained ring are considerably more discriminating in their compatibility with metathesis catalysts and as a rule require relatively high catalyst charges. In the aliphatic series, unsaturated esters have received the most attention. Boelhouwer reported in 1972 the metathesis of the ester methyl oleate and its trans isomer, methyl elaidate, with a homogeneous catalyst based on a 1/1.4 molar combination of WCl6/(CH3)4Sn (23). At 70°C and an ester/W molar ratio of 33, near-thermodynamic equilibrium was attained, and 49 and 52% of the respective esters were converted to equal amounts of 9-octadecene and the dimethyl ester of 9-octadecene-1,18-dioic acid. 

Cross-metathesis of methyl oleate with 3-hexene under similar conditions led, in addition to the above products [Eq. (54)], to 3-dodecene and the methyl ester of 9-dodecenoic acid. 

The oxidation of nonsaturated esters with double bonds far away from the ester group occurs like the oxidation of olefins (see Chapter 2). Esters like methyl oleate have weak bonds near the double bond. The peroxyl radical attacks these bonds, and the oxidation reaction occurs far from the ester group. The ester group influences the oxidation rate through its solvent properties. 

Recently an analogous mechanism for cyclic chain termination has been established for quinones [47], Quinones, which can act as acceptors of alkyl radicals, do not practically retard the oxidation of hydrocarbons at concentrations of up to 5 x 10 3 mol L 1, because the alkyl radicals react very rapidly with dioxygen. However, the ternary system, /V-phenylquinonc imine (Q) + H202 + acid (HA), efficiently retards the initiated oxidation of methyl oleate and ethylbenzene [47]. This is indicated by the following results obtained for the oxidation of ethylbenzene (343 K, p02 = 98 kPa, Vi = 5.21 x 10-7 mol L 1 s 1). 

In 1977, Kellogg and Fridovich [28] showed that superoxide produced by the XO-acetaldehyde system initiated the oxidation of liposomes and hemolysis of erythrocytes. Lipid peroxidation was inhibited by SOD and catalase but not the hydroxyl radical scavenger mannitol. Gutteridge et al. [29] showed that the superoxide-generating system (aldehyde-XO) oxidized lipid micelles and decomposed deoxyribose. Superoxide and iron ions are apparently involved in the NADPH-dependent lipid peroxidation in human placental mitochondria [30], Ohyashiki and Nunomura [31] have found that the ferric ion-dependent lipid peroxidation of phospholipid liposomes was enhanced under acidic conditions (from pH 7.4 to 5.5). This reaction was inhibited by SOD, catalase, and hydroxyl radical scavengers. Ohyashiki and Nunomura suggested that superoxide, hydrogen peroxide, and hydroxyl radicals participate in the initiation of liposome oxidation. It has also been shown [32] that SOD inhibited the chain oxidation of methyl linoleate (but not methyl oleate) in phosphate buffer. 

Methyl octyl ketone, dl9 Methyl oleate, m347 o-Methylolphenol, hi06 2-Methyloxacyclopropane, p232 Methyl oxirane, p232... 

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