Copper-Mediated Controlled Copolymerization of Methyl Acrylate with 1-Alkenes under Mild Conditions

Geometry Constrained N-(5,6,7-Trihydroquinolin-8-ylidene)arylaminopalladium Dichloride Complexes: Catalytic Behavior toward Methyl Acrylate (MA), Methyl Acrylate-co-Norbornene (MA-co-NB) Polymerization and Heck Coupling

“…Furthermore, the methoxy (-OCH3), methine (-CH) and methylene (-CH2-) signals in spectrum (b), (c) and (d) were slightly shifted toward higher field as compared to spectrum (a), verifying that the copolymerization had happened. A similar observation was reported by Wu and his co-workers [35,36]: NB are highly Similarly, for comparison 13 C-NMR spectra of PMA and MA-co-NB copolymer with different feed ratios (9/1, 7/3 and 5/5) are compiled together in Figure 5 and interpreted according to the literature [65]. The peaks for the carbonyl (-C(O)OMe), methoxy (-OCH 3 ), methine (-CH) and methylene (-CH 2 -) carbons of PMA appear at 175.0 ppm, 51.8 ppm, 41.8 ppm and 35.0 ppm, respectively.…”

“…Furthermore, the methoxy (-OCH3), methine (-CH) and methylene (-CH2-) signals in spectrum (b), (c) and (d) were slightly shifted toward higher field as compared to spectrum (a), verifying that the copolymerization had happened. A similar observation was reported by Wu and his co-workers [35,36]: NB are highly polymers. Further confirmation of copolymer formation was obtained from the by 1 H-and 13 C-NMR spectrum (vide infra, Figures 4 and 5) [37,38].…”

“…Likewise Pd5 showed slightly higher conversion of MA as compared to Pd4 and a similar correlation was observed by comparing the complexes Pd3 with Pd2 or Pd1. Contrary to Wu et al's observations [35,36], sterically hindered Pd5 gave improved conversion, so it seemed a ligand effect was involved during the initial insertion of the MA monomer. Considering the molecular weight of the obtained polymers (Figure 3), Pd5 gave the highest molecular weight, up to 6282 kg·mol −1 .…”

“…According to the mechanistic studies of Albéniz et al, free radicals were produced by light induced-homolytic cleavage of the Pd-C bond after the incorporation of one MA unit into the Pd-C 6 F 5 bond of 1 [60]. A similar mechanistic pathway was also proposed by Ye et al [35]. Although at this stage less experimental evidence is available, we reason that radicals were similarly produced from the light induced-decomposition of the palladium complex intermediate after initial incorporation of MA monomer into the palladium active species.…”

“…For instance, the copolymerization of polar monomers, particularly methyl acrylate (MA), with olefins confers novel properties on the resulting polymers: improved thermal stability, superior etch resistance, good adhesion due to the ester groups and a hydrophobic character derived from the C-C backbone [31][32][33]. Although recent progress in polymerization based on palladium catalysts allows the efficient copolymerization of polar and nonpolar monomers, the catalyst activity and second monomer insertion ratio remain quite low [34][35][36][37]. Subsequently, the design of suitable catalyst systems for efficient copolymerization of polar and non-polar monomers viz.…”