Insights into the Deactivation of Neutral Nickel Ethylene Polymerization Catalysts in the Presence of Functionalized Olefins

Abstract

Materials and Methods. All reactions were set up in a nitrogen glovebox. Methyl acrylate, and allylbenzene were purchased from the Sigma-Aldrich Chemical Company, Milwaukee, WI. They were dried over CaH 2 and distilled under reduced pressure. Methyl acrylate 2,3,3-d 3 and toluene-d 8 were purchased from Cambridge Isotope Laboratories, Inc., Andover, MA. Methyl acrylate 2,3,3-d 3 was used as received. Toluene-d 8 was dried over Na 0 /benzophenone and distilled under reduced pressure. The synthesis of compound 1 is described elsewhere.1 1 H spectra were recorded on a Varian Mercury 300 spectrometer (at 300 MHz). GC-MS data were obtained on an HP 5890 GC with an Agilent DB-5MS+DG column, and an HP 5970 EI mass selective detector. The GC was operated with the following oven program: begin at 70 °C, heat to 270 °C at a rate of 15 °C/min., maintain for 5 min., return to 70 °C at a rate of 50 °C/min. The GC traces of methyl cinnamate (2) and methyl 3-phenylpropionate (3) were confirmed by comparison with authentic samples, obtained from Sigma-Aldrich and Lancaster Synthesis, Pelham, NH, respectively. The identities of methyl phenylacrylate 2 and methyl 2-phenylpropionate 3 were confirmed by independent synthesis. The identities of the products of reaction between 1 and allylbenzene (six isomers of 1,3-diphenylpropylene and two isomers of 1,3-diphenylpropane) were confirmed by their mass spectra in the GC-MS spectrum.4 MALDI/TOF spectra were obtained with an Applied Biosystems Voyager DE PRO with a 20 Hz N 2 laser. The matrix was dithranol (5 mg/mL) in acetonitrile and was used in twofold excess relative to analyte.

Customizing Polyolefin Morphology by Selective Pairing of Alkali Ions with Nickel Phenoxyimine-Polyethylene Glycol Catalysts

“…In contrast, the solution of 3c-Na remained the same bright orange before and after polymerization. Grubbs and co-workers have reported previously that the formation of nickel bis­(phenoxyimine) ligand complexes is a common catalyst deactivation pathway . Alternatively, Mecking and co-workers have proposed that bimolecular elimination of nickel alkyl and/or nickel hydride species can also be major decomposition routes .…”

“…When polar olefins such as VA and AA were added to a solution containing 3d /B­(C 6 F 5 ) 3 , the initial bright orange solution became noticeably lighter in color. Surprisingly, upon further exposure to ethylene for up to 16 h, no polymer products were obtaind. , The change in solution color and the absence of polymerization activity suggest that 3d is not stable in the presence of polar vinyl olefins.…”

Synthesis of anilinonaphthoquinone-based nickel complexes and their application for olefin polymerization

“…In these systems, neutral nickel complexes with five-membered-ring chelating structure such as anilinotoropone [29][30][31] and anilinoperinaphthenone [32] ligands showed higher activity for ethylene polymerization than those with six-membered ones. Although it is not obvious how the chelate size affects the catalytic activities, the decrease in polymerization activity was observed with the expansion of chelate size in the other systems reported by Keim and Schulz [33], Grubbs and coworkers [10][11][12][13][14], and Brookhart [29][30][31][32].…”

“…Neutral nickel catalysts have attracted much attention, because they show good activities for olefin polymerization without any cocatalysts [10][11][12][13][14]. These catalysts are tolerant for polar solvents such as water, therefore they are useful for copolymerization of olefin with polar monomers [15][16][17] and emulsion polymerizations [18][19][20][21][22][23][24][25][26][27][28].…”

Ethylene Polymerization and Copolymerization with Polar Monomers Using Nickel Complexes Bearing Anilinobenzoic Acid Methyl Ester Ligand

“…Early examples of SHOP type neutral nickel catalysts have been commercialized for the synthesis of α-olefins [22,23,24]. A series of neutral nickel catalysts bearing salicylaldimine ligands (Chart 1 A ) was reported by Grubbs et al, which showed excellent tolerance towards polar monomers to give functionalized polyethylene [25,26,27,28]. The β-ketoiminato neutral nickel complexes with six-membered-ring were synthesized and applied as the olefin ( co )polymerization catalyst (Chart 1 B ) [29,30,31,32,33,34,35,36,37].…”