Selective CC Linkage Reactions

The first investigations concerning the hydroformylation of fatty compounds were accomplished by Ucciani and co-workers with cobalt catalysts such as cobalt bislaurate and dicobalt octacarbonyl [29]. Later, Frankel and co-workers found that the cobalt-catalyzed hydroformylation of methyl oleate also leads to the corresponding fatty alcohols [30]. In recent investigations on the hydroformylation of fatty compounds, the preferred catalyst is based on rhodium. For instance, the hydroformylation of methyl oleate catalyzed by [Rh(acac)(CO)2]/biphephos yields an isomeric mixture of formylstearic add methyl esters [31]. 

A particularly ambitious synthesis is isomerizing hydroformylation (Equation 3.1). In this reaction, first the internal double bond of the methyl oleate isomerizes to the terminal position, which is then hydroformylated to the co-aldehyde [32], 

This co-unsaturated ester is an excellent substrate for a number of important polymers It can be converted into a Cn-dicarboxylic acid, which can be utilized for the manufadure of polyesters, or into 10-aminodecanoic add, which leads to nylon 10. The epoxidation of the terminal double bond provides 9,10-epoxydecanoic acid, which can be used for the production of epoxy resins. 

Other exemplary reactions are the cross-metathesis of methyl oleate with allylam-ine, methyl acrylate and dimethyl maleate. In just a single reaction step, very different multifundional products can be produced in this way. 

---