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Updated: Jun 10, 2026

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
An efficient yttrium catalysed version of the "Aufbaureaktion" for the synthesis of terminal functionalised
Winfried P Kretschmer1, Tobias Bauer, Bart Hessen
1Stratingh Institute for Chemistry, Centre for Catalytic Olefin Polymerisation, University of Groningen, Nijenborgh, 4 NL-9747, AG, Groningen, The Netherlands. Winfried.Kretschmer@unibayreuth.de
Abstract:
The cationic lanthanoid alkyl complexes (NCN)YR(THF)(+) (R = CH(2)SiMe(3)) bearing a NCN-ligand based on N,N'-bis(2,6-diisopropylphenyl)-benzamidine (AmH), N-[6-(2,4,6-triisopropyl-phenyl)-pyridin-2-yl]-(2,6-diisopropyl)aniline (ApH) or 1,3-bis(2,6-diisopropylphenyl)-2,2-dimethylguanidine (GuaH) combined with an excess of trialkyl aluminium compounds (AlR(3); R = Et, iso-Bu, n-Oct) are efficient catalysts for the highly controlled coordinative chain transfer polymerisation (CCTP) of ethylene, a catalysed version of the "Aufbaureaktion". The aluminium terminated polyethylene (PE) can be oxidised to yield long chain alcohols which are the basis for a diverse polymer chemistry.
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