Cross-metathesis with Acrylate Derivatives

Application of RCM to acrylates derived from terpene aldehydes containing a remote double bond yielded the 6-substituted dihydropyran-2-ones <01TL6069> and oxabicyclo-[3.2.1]octane undergoes an efficient ring-opening cross-metathesis with electron-rich alkenes to give unsymmetrically 2,6-disubstituted tetrahydropyran-4-ones <01OL4275>. 

The functionalization of SAMs via ruthenium-catalyzed cross metathesis of vinyl-terminated SAMs has been reported by Lee et al.76 to install a variety of acrylic derivatives on SAMs bearing vinyl groups on their outer surface. The major drawback of this approach is the intra-SAM metathesis which causes the formation of a mixture of surface-bound products, limiting the reproducibility of the method. The formation of urethanes by the reaction of diisocyanates77 or isothiocyanates78 with hydroxyl- and amino-terminated SAMs has been reported as well. The reaction of hydroxyl-terminated SAMs with diisocyanates, allowed the preparation of isocyanate SAMs that proved to be reactive towards amines, alcohols, and water, displaying the standard chemistry of the isocyanate groups.77... 

Kolb and Meier [43] prepared a malonate derivative of methyl 10-undecenoate, which was polymerised further with 1,6-hexanediol using titanium (IV) isopropoxide as a catalyst. This polymalonate, bearing a C9 aliphatic side chain with terminal double bonds, was then subjected to grafting by ruthenium-catalysed cross-metathesis reactions with acrylates or thiol-ene addition reactions. This functionalisation enabled a subsequent Passerini multi-component reaction [44] using the pendant carboxylic-acid moiety of the modified polymers that resulted from the thiol-ene addition of 3-mercaptopropionic acid into the initial double bonds of the polymer. 

Another divergent approach was demonstrated by the use of castor oil-derived platform chemicals. Here, 10-undecenal, 10-undecenoic acid, and 10-isocyanodec-1-ene served as components for the formation of the core unit via Passerini-3CR [59]. The resulting product, having three terminal olefins, was subsequently reacted with an excess of ferf-butyl acrylate in a cross-metathesis reaction, followed by hydrogenation of the newly formed double bonds. The introduced tert-hvXy esters were cleaved with trifiuoroacetic acid thus, three carboxylic acid groups were... 

Rybak A, Meier MAR. 2007. Cross-metathesis of fatty acid derivatives with methyl acrylate renewable raw materials for the chemical industry. Green Chem 9 1356-1361. 

Water-soluble mthenium vinyUdene and aUenylidene complexes were also synthetized in the reaction of [ RuCl2(TPPMS)2 2] and phenylacetylene or diphenylpropargyl alcohol [29]. The mononuclear Ru-vinylidene complex [RuCl2 C=C(H)Ph)(TPPMS)2] and the dinuclear Ru-aUylidene derivative [ RuCl(p,-Cl)(C=C=CPh2)(TPPMS)2 2] both catalyzed the cross-olefin metathesis of cyclopentene with methyl acrylate to give polyunsaturated esters under mild conditions (Scheme 7.10). 

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