Structure–Activity Relationship of Palladium Phosphanesulfonates: Toward Highly Active Palladium‐Based Polymerization Catalysts

Abstract

Palladium phosphanesulfonate [R(2)P(C(6)H(4)-o-SO(3))PdMeL] catalysts permit the copolymerization of an exceptional large number of functional olefins with ethylene. However, these catalysts usually have reduced activity. We here have conducted a systematic study on the influence of the phosphane substituent, R, on activity and molecular weight. Phosphanes with strong σ-donating character are shown to lead to the most active catalysts. Thus, the catalyst based on phosphane bis-tert-butyl-phosphanyl-benzenesulfonic acid (R=tBu) exhibits unprecedented high activity, rapidly polymerizing ethylene at room temperature to yield a linear polymer of high molecular weight (M(w)=116,000 g mol(-1)). The influence of the R group on the catalyst ability to incorporate methyl acrylate is also investigated.

Synthesis and Applications in Catalysis of Metal Complexes with Chelating Phosphinosulfonate Ligands

“…6 Then, well-defined nickel(II) catalysts were prepared featuring one or two bidentate ligands (Scheme 3.53). 13,54,110,111 Both negative and positive effects were obtained and high activity was reached when one of the aryl group was replaced by a tert-butyl group. 15,67,68,71 More studies report on the use of palladium catalysts for ethylene homopolymerization.…”

“…In all cases, good catalytic activities were obtained in ethylene polymerization producing various materials depending on the conditions. 54 In the presence of a second pendant sulfonate group on the bidentate ligand, self-assembled polynuclear palladium species can be formed and this aggregation had a strong influence on ethylene polymerization. With organopalladium systems equipped with a bidentate phosphinosulfonate ligand, productive catalytic systems are obtained leading to highly linear polyethylenes.…”

Influence of Ligand Backbone Structure and Connectivity on the Properties of Phosphine-Sulfonate Pd(II)/Ni(II) Catalysts

“…Among the numerous late transition metal catalysts, the Brookhart type α-diimine Ni(II) and Pd(II) [1][2][3][4][5][6][7][8][9][10][11][12][13][14], phenoxyminato based Ni(II) [15][16][17][18][19][20][21] and the phosphine-sulfonate Pd(II) catalysts [22][23][24][25][26][27][28][29][30][31][32][33][34][35] are the most extensively studied systems. It has been demonstrated that the properties of these catalysts are very sensitive to the ligand sterics.…”

A highly active and thermally stable 6,13-dihydro-6,13-ethanopentacene-15,16-diimine nickel(ii) complex as catalyst for norbornene polymerization

“…[1][2][3] It is well-known that the NB polymerization reaction can be efficiently carried out using conventional Ziegler-Natta catalysts, 4,5 metallocene catalysts 6,7 and late-transition metal catalysts. [8][9][10][11][12][13][14] Recently, the latetransition metal catalysts have shown lower oxophilicity and resistance toward polar functionalities, which resulted in renewed interest. The common late transition metal catalysts are nickel(II) and palladium(II) complexes.…”