Methyl oleate, ozonolysis

Methyl 9-hydroxynonanoate H0(CH2)8C00CH3 Methyl oleate Ozonolysis Liu et al. (2008)... 

Reduction of ozonides is very useful, especially when aldehydes are the desired products. Ozonides are easily hydrogenolyzed over palladium [670], or reduced by zinc in acetic acid [671], usually in good yields. Ozonolysis of methyl oleate followed by hydrogenation over 10% palladium on charcoal... 

Rebrovic, L., The Peroxidic Species Generated by Ozonolysis of Oleic Acid or Methyl Oleate in a Carboxyhc Acid Medium,/. Am. Oil Chem. Soc. 69 159-165 (1992). 

The products of the two types of reaction can be identified on almost any GC column or phase difunctional compounds are more rapidly eluted on silicone liquid phases, but are less likely to be confused with mono-functional compounds on polyester phases. With both types of liquid phase, temperature-programmed analysis is generally necessary if all the fragments must be determined. Dicarboxylic acid standards are readily available for comparison, but aldehydo-esters are not and it may be necessary to make up a suitable standard by ozonolysis of monoenoic esters of known stmcture that are commercially available, e.g. methyl petroselinate, methyl oleate and methyl vaccenate. A GC trace of the ozonolysis products of such a mixture on an EGS column is illustrated in Figure 6.13. 

Methyl oleate 6 was among the first unsaturated esters to be examined by Bickford et The reaction was conducted at 220°C, under a carbon dioxide atmosphere for 2 h. A structure was speculated on, again, involving allylic hydrogen. An ozonolysis study of the reaction product gave no conclusive information. Ross et showed, based on oxidation of the products, that the reaction produces a succinic acid derivative by first attack at either the 9 or 10 position of methyl oleate 6 with consequent migration of the double bond to the adjacent 10,11 or 8,9 positions, respectively. 

More recently various olefins were converted in a single-step reaction to methyl esters by ozonolysis in the presence of sodium methoxide. Such reactions were previously demonstrated with unsaturated ethers, esters, and amides including the reaction of methyl oleate to methyl nonanoate and dimethyl nonanedioate (Figure 2). It was concluded that this one-step conversion of olefins to methyl esters in basic methanol solution appears to be general and does not depend on a required structure or a strained bond of the reactants. 

Ph cH3 CH30-Na V cH3 CH3M7CH3 Figure 2 Ozonolysis of methyl oleate in sodium methoxide solution... 

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