Imidazolinium salts as catalysts for the ring-opening alkylation of meso epoxides by alkylaluminum complexes.
[reaction: see text] Imidazolinium salts and their N-heterocyclic carbene (NHC) derivatives catalyze the alkylation of a variety of meso epoxides in the presence of triethylaluminum (yield = 70-90%), under mild conditions. Imidazolinium salts are better catalysts than their NHC derivatives but can lead to dimerization side reactions under extended reaction time. Preformed NHC.AlEt(3) complexes and Wanzlick-type olefins, which are dimers of free NHCs, are also catalysts for this reaction.
Zhou
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Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA.
Campbell
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EJ
Nguyen
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