Alkylidene-Ruthenium-Tin Catalysts for the Formation of Fatty Nitriles and Esters via Cross-Metathesis of Plant Oil Derivatives

Abstract

The reaction of SnCl 2 with the Ru-Cl bond of the Grubbs I catalyst RuCl 2 (dCHPh)(PCy 3 ) 2 (1) gives the complex {[Ru(dCHPhbut containing two diethyl ether solvate molecules. The formal insertion of SnCl 2 into one Ru-Cl bond of the Hoveyda II catalyst RuCl 2 (dCH-C 6 H 4 OPrin formation of the new complex RuCl(SnCl 3 )(dCH-C 6 H 4 OPr i )(H 2 IMes) (4). The X-ray analyses of 2 and 4 show the presence of very short Ru-Sn bonds (2.5834(9) A ˚mean bond for 2 and 2.5925(12) A ˚for 4) and the retention of short RudC bonds (1.895(10) and 1.825(8) A ˚, respectively). Complex 4 shows an excellent catalytic activity for the cross-metathesis of plant oil derivatives, the C11 ω-unsaturated ester and aldehyde and the unsaturated C18 diester with acrylonitrile, and a good activity for their cross-metathesis with methyl acrylate. Good to excellent yield of R,ω-bifunctional compounds, precursors of polyesters and polyamides, were obtained. Complex 2 shows catalytic activity for the self-metathesis of C11 ω-unsaturated aldehyde at low concentration to produce C20 R,ω-dialdehyde.

Synthesis and Properties of Bimetallic Hoveyda–Grubbs Metathesis Catalysts

“…The results revealed severe selectivity problems, in accord with the results of our synthetic attempts. Reactions with ligands 22 and 19a displayed the gradual disappearance of the substrate complex 2 and the development of one sharp resonance (19a), or a set of overlapping resonances around 16.5 ppm (22). In turn, reactions with ligands 30 and 27, corresponding to the tricyclic Figure 1.…”

Metathesis of renewable raw materials—influence of ligands in the indenylidene type catalysts on self-metathesis of methyl oleate and cross-metathesis of methyl oleate with (Z)-2-butene-1,4-diol diacetate

“…13,14 Great attention in recent years has been also devoted to cross-metathesis (CM) because of the possibility of creating olefins with different functional groups. [15][16][17] CM is also possible with electron-poor reagents such as vinyl sulfones, 18 acrylonitrile, 19,20 methyl acrylate, 21,22 and others. This makes it possible to obtain a wide range of bifunctional olefins.…”

Cross-metathesis of methyl 10-undecenoate with dimethyl maleate: an efficient protocol with nearly quantitative yields

“…[21][22][23] This substrate is both the asymmetrical analogue to dimethyl maleate 2 and a widely-used cosubstrate in oleochemistry. 16,[24][25][26][27][28][29][30] The self metathesis of methyl 10-undecenoate 1 to dimethyl icos-10-enedioate 5 through the release of ethylene was the only side reaction observed for the cross metathesis in question (Fig. 2).…”

“…31 Different methods for the cross metathesis of fatty-derivatives have been published. Several of the cosubstrates include allylchloride, 25 acrylo-and fumaronitril, 25,26,32,33 acrolein, 34 ethyl acrylate 35 and cis-2-buten-1,4-diyl diacetate. 36 However, only a few means of cross metathesis with symmetrical maleate esters have been published to this day.…”