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Preparation of Mixed Bis-N-Heterocyclic Carbene Rhodium(I) Complexes.

ABSTRACT: A series of mixed bis-NHC rhodium(I) complexes of type RhCl(η²-olefin)(NHC)(NHC') have been synthesized by a stepwise reaction of [Rh(μ-Cl)(η²-olefin)₂]₂ with two different NHCs (NHC = N-heterocyclic carbene), in which the steric hindrance of both NHC ligands and the η²-olefin is critical. Similarly, new mixed coumarin-functionalized bis-NHC rhodium complexes have been prepared by a reaction of mono NHC complexes of type RhCl(NHC-coumarin)(η²,η²-cod) with the corresponding azolium salt in the presence of an external base. Both synthetic procedures proceed selectively and allow the preparation of mixed bis-NHC rhodium complexes in good yields.

SUBMITTER: Azpiroz R

PROVIDER: S-EPMC9611579 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature

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Preparation of Mixed Bis-N-Heterocyclic Carbene Rhodium(I) Complexes.

Azpíroz Ramón R Karataş Mert Olgun MO Passarelli Vincenzo V Özdemir Ismail I Pérez-Torrente Jesús J JJ Castarlenas Ricardo R

Molecules (Basel, Switzerland) 20221018 20

A series of mixed bis-NHC rhodium(I) complexes of type RhCl(η2-olefin)(NHC)(NHC') have been synthesized by a stepwise reaction of [Rh(μ-Cl)(η2-olefin)2]2 with two different NHCs (NHC = N-heterocyclic carbene), in which the steric hindrance of both NHC ligands and the η2-olefin is critical. Similarly, new mixed coumarin-functionalized bis-NHC rhodium complexes have been prepared by a reaction of mono NHC complexes of type RhCl(NHC-coum ...[more]

PMID: 36296594

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