Synthesis and Reactions of Palladium and Platinum Complexes Bearing Diphosphinidenecyclobutene Ligands: A Thermally Stable Catalyst for Ethylene Polymerization

Abstract

A cationic methylpalladium complex bearing a diphosphinidenecyclobutene ligand generated by the treatment of the corresponding dimethyl complex 1 with H(OEt2)2[BAr4] (Ar=3,5‐(CF3)2C6H3), exhibits good catalytic activity for ethylene polymerization in solution (up to 128 kg h−1 (mol cat.)−1). The catalyst is thermally stable and promotes the polymerization even at 100 °C without notable decomposition.

Phosphaalkene, phospholyl and phosphinine ligands: New tools in coordination chemistry and catalysis

“…More convincing results were obtained in the ethylene polymerisation process with complexes complexes such as 278-279 (Figure 54). The most promising results were obtained with the 1,2-diaryl-3,4-diphosphinidene cyclobutene ligands DCPB-Y (Y stands for the functional group grafted at the para position of the aryl substituent) [220]. Similarly to diimine-Pd complexes, PdMe 2 complexes were found to be inactive but their corresponding cationic monomethyl complexes which were generated in situ by treatment with H(OEt 2 ) 2 BAr 4 (Ar = (CF 3 ) 2 C 6 H 3 ) showed a good activity.…”

Chemistry of Several Sterically Bulky Molecules with P=P, P=C, and C≡P Bond

“…As expected, DPCB 82 is a good bidentate ligand for transition metals such as chromium, molybdenum, tungsten, iron, gold, palladium, platinum, rhodium. Scheme 32 shows several typical examples ( 90 – 94 ) that have been analyzed in X-ray studies [ 97 , 98 , 99 , 100 , 101 , 102 , 103 ]. It is noteworthy that the molecular structure of 94 shows that the π-allyl system is perpendicular to the DPCB plane, which controls the stereochemistry in the catalytic reactions.…”

Phosphorheterocyclen: von Laborkuriositäten zu Liganden in hocheffizienten Katalysatoren

“…Die Dimethylpalladiumkomplexe 49 b und 49 c entstehen bei der Reaktion von [PdMe 2 (tmeda)] mit den Diphosphinidencyclobutenen 21 b und c in 94 bzw. 63 % Ausbeute, während zur Herstellung von 49 a [PdMe 2 (cod)] als Ausgangsmaterial erforderlich war (60 % Ausbeute; Schema ) 43…”