Synthesis of Chiral C ₁-Symmetric N-Heterocyclic Carbene Ligands: Application toward Copper-Catalyzed Homocoupling of 2-Naphthols

Abstract

Novel chiral C ₁-symmetric NHC ligands can be prepared via dialkylation of chiral imidazoline scaffolds. Asymmetry in the ligand/metal complexes results from a chiral relay effect. The C ₁-symmetric nature of the NHC ligand was proposed to allow for improved reactivity versus other achiral and chiral NHC complexes. The benefit of such ligands was demonstrated in copper-catalyzed oxidative coupling reactions.

Key words

oxidative coupling - binaphthols - N-heterocyclic carbenes - copper - catalysis

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