As low as reasonably achievable catalyst loadings in the cross metathesis of olefins with ethyl acrylate

Optimized reaction conditions for the cross-metathesis of methyl oleate and oleylamine with ethyl acrylate

“…Technical quality was chosen because use of highly purified fatty acid derivatives cannot be regarded as being as ''green'' as such products. As the starting point of the studies presented here, reaction conditions developed for the cross-metathesis of 1,9-decadiene with ethyl acrylate were adopted on the basis of considerations based on findings published elsewhere [12]. Assuming that the transformation of internal double bonds is harder to achieve than the conversion of terminal double bonds, a larger amount of catalyst (0.1 mol% relative to 4) was used initially.…”

“…Accordingly, BHT (1 mol% relative to 4) was added to the reaction mixtures for the same purpose. The best performing species from previous work were selected as catalysts [12]. The standard catalyst for this kind of transformation is 1 [6,7] and 2 is a closely related alternative to 1.…”

“…This behaviour can be understood as the need for a preceding isomerization reaction to convert the metathesis-inactive cis-dichloro species into the corresponding metathetically active trans-dichloro species [13]. Catalyst 3 enabled use of the lowest catalyst loading in the cross-metathesis of 1,9-decadiene and 5 [12]. Results from cross-metathesis of 4 with 5 by use of different catalysts are shown in Table 1 and the reaction is depicted in Scheme 1.…”

“…Although the exact nature of this polymer is unknown it is most probably derived from radical polymerization of 5 (for characterization see Ref. [12]). Nevertheless, it seems that 6 and 7 are incorporated into this polymer.…”

Converting natural rubber waste into ring-opening metathesis polymers with oligo-1,4-cis-isoprene sidechains

“…Furthermore, the reaction was carried out in neat ethyl acrylate since it has been shown that under such conditions particularly low catalyst loadings could be achieved. 13 However, in the case of NR as the substrate, only sluggish degradation but pronounced dimerization of ethyl acrylate forming diethyl fumarate 14 was noted. The use of methyl acrylate instead of ethyl acrylate resulted in similar m values but distinctly higher fumarate ratios as well as lower yields.…”