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Titolo:
New C-2v- and chiral C-2-symmetric olefin polymerization catalysts based on nickel(II) and palladium(II) diimine complexes bearing 2,6-diphenyl aniline moieties: Synthesis, structural characterization, and first insight intopolymerization properties
Autore:
Schmid, M; Eberhardt, R; Klinga, M; Leskela, M; Rieger, B;
Indirizzi:
Univ Ulm, Dept Mat & Catalysis, D-89069 Ulm, Germany Univ Ulm Ulm Germany D-89069 Dept Mat & Catalysis, D-89069 Ulm, Germany Univ Helsinki, Dept Chem, FIN-00014 Helsinki, Finland Univ Helsinki Helsinki Finland FIN-00014 em, FIN-00014 Helsinki, Finland
Titolo Testata:
ORGANOMETALLICS
fascicolo: 11, volume: 20, anno: 2001,
pagine: 2321 - 2330
SICI:
0276-7333(20010528)20:11<2321:NCACCO>2.0.ZU;2-V
Fonte:
ISI
Lingua:
ENG
Soggetto:
ETHYLENE; CHEMISTRY; COBALT; IRON;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
29
Recensione:
Indirizzi per estratti:
Indirizzo: Rieger, B Univ Ulm, Dept Mat & Catalysis, D-89069 Ulm, Germany Univ Ulm Ulm Germany D-89069 & Catalysis, D-89069 Ulm, Germany
Citazione:
M. Schmid et al., "New C-2v- and chiral C-2-symmetric olefin polymerization catalysts based on nickel(II) and palladium(II) diimine complexes bearing 2,6-diphenyl aniline moieties: Synthesis, structural characterization, and first insight intopolymerization properties", ORGANOMETAL, 20(11), 2001, pp. 2321-2330

Abstract

Four new 1,4-diaza-2,3-dimethylbutadiene ligands (Ar-N=C(CH3)-(H3C)C=NAr; Ar: 3a = 2,6-diphenylphenyl; 3b = 2,6-di(4-OCH3-phenyl)phenyl; 3c = 2,6-di(4-tert-butyl-phenyl)-phenyl; 3d = 2,6-di(3,5-dimethylphenyl)phenyl) as wellas the palladium dichloride complexes 4a-c and methyl monochloride derivatives 5a-c,were prepared, and their polymerization behavior was investigated. The corresponding nickel species 6a-c were tested for the insertion polymerization of ethene by in situ reactions of 3a-c with (DME)NiBr2. The ligands are accessible by a three-step procedure. Aryl boronic acids were prepared by Grignard reactions of substituted aryl bromides and were coupled,with2,6-dibromo aniline according to a Suzuki cross-coupling protocol to give the corresponding terphenyl anilines 2a-d. Condensation of 2,3-butanedione with the corresponding aniline afforded the formation of the diimines 3a-d;The corresponding palladium dichloride complexes 4a-e are-accessible by reaction with (PhCN)(2)PdCl2. The structures of 4a-e could be determined by X-ray analysis. While the terphenyl complex 4a adopts a C-2v-symmetry, 4c exists in a chiral C-2-symmetric coordination geometry, due: to the repulsiveinteractions of the sterically demanding tert-butylphenyl substituents of the aniline moieties. All palladium and nickel complexes are catalysts for the polymerization of ethene. However, the chiral NI(II) complex ww6c showsby far the highest polymerization activity up to 2 x 10(4) kg(PE) [mol (Ni) h](-1). The polyethenes obtained with the palladium methyl monochloro catalysts activated with Na[(3,5-(CF3)(2)C6H3)(4)B] and the nickel dibromo complexes activated with MAO are linear and show in the case of the Ni(II)derivatives molecular weights up to 4.5 x 10(6) g mol(-1) (M-w/M-n approximate to 2), which can be controlled by addition of hydrogen.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 22/10/20 alle ore 09:25:58