307933-40-0Relevant academic research and scientific papers
Dicationic ruthenium(II) complexes containing bridged η1:η6-phosphinoarene ligands for the ring-opening metathesis polymerization
Abele, Alexandra,Wursche, Roland,Klinga, Martti,Rieger, Bernhard
, p. 23 - 33 (2000)
Tertiary phosphines with pendant genes R2PR' (R = Cy, Ph; R' = CH2CH2Ph or CH2CHPh2) (1-4) were synthesized and converted to the corresponding chelating ruthenium(II) complexes [RuCl2(η1:η6-R2PR')] (1a-4a). Halide exchange yielded [RuI2(η1:η6-R2PR')] (1b,3b), which were structurally characterized by single crystal X-ray diffraction. The systems (1a,2a,4a) were activated for ROMP of norbomene by addition of a diazo compound (trimethylsilyldiazomethane) and AgBF4 (A), by a diazo compound alone (B) or by a combination of the sodium salt NaB(Ar(f))4(Ar(f) = 3,5-(CF3)2C6H3) and methanol (C). The influence of the thereby created differing number of accessible coordination sites on the polymerization activity and the polymer microstructure (cis/trans ratio) was investigated. The nucleophilicity of the counter ion was found to play a crucial role in terms of catalytic activity. (C) 2000 Elsevier Science B.V.
