Monocyclopentadienyl complexes in which the cyclopentadienyl system bears at least one unsubstituted, substituted or fused, heteroaromatic ring system bound via a specific bridge, a catalyst system comprising at least one of the monocyclopentadienyl complexes, the use of the catalyst system for the polymerization or copolymerization of olefins and a process for preparing polyolefins by polymerization or copolymerization of olefins in the presence of the catalyst system and polymers obtainable in this way.
Activation of monocyclopentadienyl group 6 complexes
申请人:Nagy Sandor
公开号:US20110213107A1
公开(公告)日:2011-09-01
A method for preparing a supported catalyst suitable for use in slurry and gas-phase olefin polymerizations is disclosed. An alumoxane-treated silica is combined with a monocyclopentadienyl Group 6 metal complex that comprises a chelating Cp moiety to give the supported catalyst. The method is simple to practice and provides catalysts having high activity. Polyolefins made using the catalysts have high molecular weight that is readily controlled by adding hydrogen.
Friedel–Crafts Reactions with <i>N</i>-Heterocyclic Alcohols
作者:Jacob C. Hood、Maksim V. Anokhin、Douglas A. Klumpp
DOI:10.1021/acs.joc.3c00403
日期:2023.8.4
N-Heterocyclic alcohols are shown to be excellent substrates for superacid-promoted Friedel–Crafts reactions. The N-heterocyclic alcohols ionize to produce reactive, dicationic intermediates which provide good to excellent yields of arylation products.